diff --git a/core/src/main/java/org/bitcoin/NativeSecp256k1.java b/core/src/main/java/org/bitcoin/NativeSecp256k1.java
index 40ae76d7c..76e090036 100644
--- a/core/src/main/java/org/bitcoin/NativeSecp256k1.java
+++ b/core/src/main/java/org/bitcoin/NativeSecp256k1.java
@@ -42,7 +42,7 @@ public class NativeSecp256k1 {
     private static final ReentrantReadWriteLock rwl = new ReentrantReadWriteLock();
     private static final Lock r = rwl.readLock();
     private static final Lock w = rwl.writeLock();
-    private static ThreadLocal<ByteBuffer> nativeECDSABuffer = new ThreadLocal<ByteBuffer>();
+    private static ThreadLocal<ByteBuffer> nativeECDSABuffer = new ThreadLocal<>();
 
     /**
      * Verifies the given secp256k1 signature in native code. Calling when enabled == false is undefined (probably
diff --git a/core/src/main/java/org/bitcoinj/core/AbstractBlockChain.java b/core/src/main/java/org/bitcoinj/core/AbstractBlockChain.java
index 04820d2fa..266ee6d20 100644
--- a/core/src/main/java/org/bitcoinj/core/AbstractBlockChain.java
+++ b/core/src/main/java/org/bitcoinj/core/AbstractBlockChain.java
@@ -121,7 +121,7 @@ public abstract class AbstractBlockChain {
     }
     // Holds blocks that we have received but can't plug into the chain yet, eg because they were created whilst we
     // were downloading the block chain.
-    private final LinkedHashMap<Sha256Hash, OrphanBlock> orphanBlocks = new LinkedHashMap<Sha256Hash, OrphanBlock>();
+    private final LinkedHashMap<Sha256Hash, OrphanBlock> orphanBlocks = new LinkedHashMap<>();
 
     /** False positive estimation uses a double exponential moving average. */
     public static final double FP_ESTIMATOR_ALPHA = 0.0001;
@@ -150,9 +150,9 @@ public abstract class AbstractBlockChain {
         log.info("chain head is at height {}:\n{}", chainHead.getHeight(), chainHead.getHeader());
         this.params = context.getParams();
 
-        this.newBestBlockListeners = new CopyOnWriteArrayList<ListenerRegistration<NewBestBlockListener>>();
-        this.reorganizeListeners = new CopyOnWriteArrayList<ListenerRegistration<ReorganizeListener>>();
-        this.transactionReceivedListeners = new CopyOnWriteArrayList<ListenerRegistration<TransactionReceivedInBlockListener>>();
+        this.newBestBlockListeners = new CopyOnWriteArrayList<>();
+        this.reorganizeListeners = new CopyOnWriteArrayList<>();
+        this.transactionReceivedListeners = new CopyOnWriteArrayList<>();
         for (NewBestBlockListener l : wallets) addNewBestBlockListener(Threading.SAME_THREAD, l);
         for (ReorganizeListener l : wallets) addReorganizeListener(Threading.SAME_THREAD, l);
         for (TransactionReceivedInBlockListener l : wallets) addTransactionReceivedListener(Threading.SAME_THREAD, l);
@@ -230,7 +230,7 @@ public abstract class AbstractBlockChain {
      * Adds a {@link NewBestBlockListener} listener to the chain.
      */
     public final void addNewBestBlockListener(Executor executor, NewBestBlockListener listener) {
-        newBestBlockListeners.add(new ListenerRegistration<NewBestBlockListener>(listener, executor));
+        newBestBlockListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -244,7 +244,7 @@ public abstract class AbstractBlockChain {
      * Adds a generic {@link ReorganizeListener} listener to the chain.
      */
     public final void addReorganizeListener(Executor executor, ReorganizeListener listener) {
-        reorganizeListeners.add(new ListenerRegistration<ReorganizeListener>(listener, executor));
+        reorganizeListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -258,7 +258,7 @@ public abstract class AbstractBlockChain {
      * Adds a generic {@link TransactionReceivedInBlockListener} listener to the chain.
      */
     public final void addTransactionReceivedListener(Executor executor, TransactionReceivedInBlockListener listener) {
-        transactionReceivedListeners.add(new ListenerRegistration<TransactionReceivedInBlockListener>(listener, executor));
+        transactionReceivedListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -506,7 +506,7 @@ public abstract class AbstractBlockChain {
     public Set<Sha256Hash> drainOrphanBlocks() {
         lock.lock();
         try {
-            Set<Sha256Hash> hashes = new HashSet<Sha256Hash>(orphanBlocks.keySet());
+            Set<Sha256Hash> hashes = new HashSet<>(orphanBlocks.keySet());
             orphanBlocks.clear();
             return hashes;
         } finally {
@@ -818,7 +818,7 @@ public abstract class AbstractBlockChain {
      */
     private static LinkedList<StoredBlock> getPartialChain(StoredBlock higher, StoredBlock lower, BlockStore store) throws BlockStoreException {
         checkArgument(higher.getHeight() > lower.getHeight(), "higher and lower are reversed");
-        LinkedList<StoredBlock> results = new LinkedList<StoredBlock>();
+        LinkedList<StoredBlock> results = new LinkedList<>();
         StoredBlock cursor = higher;
         while (true) {
             results.add(cursor);
diff --git a/core/src/main/java/org/bitcoinj/core/AddressMessage.java b/core/src/main/java/org/bitcoinj/core/AddressMessage.java
index b4053852d..9ef091496 100644
--- a/core/src/main/java/org/bitcoinj/core/AddressMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/AddressMessage.java
@@ -76,7 +76,7 @@ public class AddressMessage extends Message {
         // Guard against ultra large messages that will crash us.
         if (numAddresses > MAX_ADDRESSES)
             throw new ProtocolException("Address message too large.");
-        addresses = new ArrayList<PeerAddress>((int) numAddresses);
+        addresses = new ArrayList<>((int) numAddresses);
         for (int i = 0; i < numAddresses; i++) {
             PeerAddress addr = new PeerAddress(params, payload, cursor, protocolVersion, this, serializer);
             addresses.add(addr);
diff --git a/core/src/main/java/org/bitcoinj/core/AlertMessage.java b/core/src/main/java/org/bitcoinj/core/AlertMessage.java
index 2e6e9e419..7c1ecc102 100644
--- a/core/src/main/java/org/bitcoinj/core/AlertMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/AlertMessage.java
@@ -87,7 +87,7 @@ public class AlertMessage extends Message {
         }
         // Using a hashset here is very inefficient given that this will normally be only one item. But Java doesn't
         // make it easy to do better. What we really want is just an array-backed set.
-        Set<Long> cancelSet = new HashSet<Long>((int) cancelSetSize);
+        Set<Long> cancelSet = new HashSet<>((int) cancelSetSize);
         for (long i = 0; i < cancelSetSize; i++) {
             cancelSet.add(readUint32());
         }
@@ -98,7 +98,7 @@ public class AlertMessage extends Message {
         if (subverSetSize < 0 || subverSetSize > MAX_SET_SIZE) {
             throw new ProtocolException("Bad subver set size: " + subverSetSize);
         }
-        Set<String> matchingSubVers = new HashSet<String>((int) subverSetSize);
+        Set<String> matchingSubVers = new HashSet<>((int) subverSetSize);
         for (long i = 0; i < subverSetSize; i++) {
             matchingSubVers.add(readStr());
         }
diff --git a/core/src/main/java/org/bitcoinj/core/BitcoinSerializer.java b/core/src/main/java/org/bitcoinj/core/BitcoinSerializer.java
index 6f68e00c6..82f8911f6 100644
--- a/core/src/main/java/org/bitcoinj/core/BitcoinSerializer.java
+++ b/core/src/main/java/org/bitcoinj/core/BitcoinSerializer.java
@@ -48,7 +48,7 @@ public class BitcoinSerializer extends MessageSerializer {
     private final NetworkParameters params;
     private final boolean parseRetain;
 
-    private static final Map<Class<? extends Message>, String> names = new HashMap<Class<? extends Message>, String>();
+    private static final Map<Class<? extends Message>, String> names = new HashMap<>();
 
     static {
         names.put(VersionMessage.class, "version");
diff --git a/core/src/main/java/org/bitcoinj/core/Block.java b/core/src/main/java/org/bitcoinj/core/Block.java
index 08b14283f..7f3d4cf3e 100644
--- a/core/src/main/java/org/bitcoinj/core/Block.java
+++ b/core/src/main/java/org/bitcoinj/core/Block.java
@@ -201,7 +201,7 @@ public class Block extends Message {
         this.time = time;
         this.difficultyTarget = difficultyTarget;
         this.nonce = nonce;
-        this.transactions = new LinkedList<Transaction>();
+        this.transactions = new LinkedList<>();
         this.transactions.addAll(transactions);
     }
 
@@ -237,7 +237,7 @@ public class Block extends Message {
 
         int numTransactions = (int) readVarInt();
         optimalEncodingMessageSize += VarInt.sizeOf(numTransactions);
-        transactions = new ArrayList<Transaction>(numTransactions);
+        transactions = new ArrayList<>(numTransactions);
         for (int i = 0; i < numTransactions; i++) {
             Transaction tx = new Transaction(params, payload, cursor, this, serializer, UNKNOWN_LENGTH);
             // Label the transaction as coming from the P2P network, so code that cares where we first saw it knows.
@@ -619,7 +619,7 @@ public class Block extends Message {
         //    2     3    4  4
         //  / \   / \   / \
         // t1 t2 t3 t4 t5 t5
-        ArrayList<byte[]> tree = new ArrayList<byte[]>();
+        ArrayList<byte[]> tree = new ArrayList<>();
         // Start by adding all the hashes of the transactions as leaves of the tree.
         for (Transaction t : transactions) {
             tree.add(t.getHash().getBytes());
@@ -760,7 +760,7 @@ public class Block extends Message {
     void addTransaction(Transaction t, boolean runSanityChecks) {
         unCacheTransactions();
         if (transactions == null) {
-            transactions = new ArrayList<Transaction>();
+            transactions = new ArrayList<>();
         }
         t.setParent(this);
         if (runSanityChecks && transactions.size() == 0 && !t.isCoinBase())
@@ -867,7 +867,7 @@ public class Block extends Message {
     @VisibleForTesting
     void addCoinbaseTransaction(byte[] pubKeyTo, Coin value, final int height) {
         unCacheTransactions();
-        transactions = new ArrayList<Transaction>();
+        transactions = new ArrayList<>();
         Transaction coinbase = new Transaction(params);
         final ScriptBuilder inputBuilder = new ScriptBuilder();
 
diff --git a/core/src/main/java/org/bitcoinj/core/BloomFilter.java b/core/src/main/java/org/bitcoinj/core/BloomFilter.java
index 9f310a19b..0e3d66151 100644
--- a/core/src/main/java/org/bitcoinj/core/BloomFilter.java
+++ b/core/src/main/java/org/bitcoinj/core/BloomFilter.java
@@ -301,7 +301,7 @@ public class BloomFilter extends Message {
      */
     public synchronized FilteredBlock applyAndUpdate(Block block) {
         List<Transaction> txns = block.getTransactions();
-        List<Sha256Hash> txHashes = new ArrayList<Sha256Hash>(txns.size());
+        List<Sha256Hash> txHashes = new ArrayList<>(txns.size());
         List<Transaction> matched = Lists.newArrayList();
         byte[] bits = new byte[(int) Math.ceil(txns.size() / 8.0)];
         for (int i = 0; i < txns.size(); i++) {
diff --git a/core/src/main/java/org/bitcoinj/core/CheckpointManager.java b/core/src/main/java/org/bitcoinj/core/CheckpointManager.java
index c9d3628c6..20a746a2e 100644
--- a/core/src/main/java/org/bitcoinj/core/CheckpointManager.java
+++ b/core/src/main/java/org/bitcoinj/core/CheckpointManager.java
@@ -76,7 +76,7 @@ public class CheckpointManager {
     private static final int MAX_SIGNATURES = 256;
 
     // Map of block header time to data.
-    protected final TreeMap<Long, StoredBlock> checkpoints = new TreeMap<Long, StoredBlock>();
+    protected final TreeMap<Long, StoredBlock> checkpoints = new TreeMap<>();
 
     protected final NetworkParameters params;
     protected final Sha256Hash dataHash;
diff --git a/core/src/main/java/org/bitcoinj/core/Context.java b/core/src/main/java/org/bitcoinj/core/Context.java
index 1f0debe85..4997f1ead 100644
--- a/core/src/main/java/org/bitcoinj/core/Context.java
+++ b/core/src/main/java/org/bitcoinj/core/Context.java
@@ -89,7 +89,7 @@ public class Context {
 
     private static volatile Context lastConstructed;
     private static boolean isStrictMode;
-    private static final ThreadLocal<Context> slot = new ThreadLocal<Context>();
+    private static final ThreadLocal<Context> slot = new ThreadLocal<>();
 
     /**
      * Returns the current context that is associated with the <b>calling thread</b>. BitcoinJ is an API that has thread
diff --git a/core/src/main/java/org/bitcoinj/core/FilteredBlock.java b/core/src/main/java/org/bitcoinj/core/FilteredBlock.java
index 84def7e4d..0e7efe18d 100644
--- a/core/src/main/java/org/bitcoinj/core/FilteredBlock.java
+++ b/core/src/main/java/org/bitcoinj/core/FilteredBlock.java
@@ -36,7 +36,7 @@ public class FilteredBlock extends Message {
     
     // A set of transactions whose hashes are a subset of getTransactionHashes()
     // These were relayed as a part of the filteredblock getdata, ie likely weren't previously received as loose transactions
-    private Map<Sha256Hash, Transaction> associatedTransactions = new HashMap<Sha256Hash, Transaction>();
+    private Map<Sha256Hash, Transaction> associatedTransactions = new HashMap<>();
     
     public FilteredBlock(NetworkParameters params, byte[] payloadBytes) throws ProtocolException {
         super(params, payloadBytes, 0);
@@ -76,7 +76,7 @@ public class FilteredBlock extends Message {
     public List<Sha256Hash> getTransactionHashes() throws VerificationException {
         if (cachedTransactionHashes != null)
             return Collections.unmodifiableList(cachedTransactionHashes);
-        List<Sha256Hash> hashesMatched = new LinkedList<Sha256Hash>();
+        List<Sha256Hash> hashesMatched = new LinkedList<>();
         if (header.getMerkleRoot().equals(merkleTree.getTxnHashAndMerkleRoot(hashesMatched))) {
             cachedTransactionHashes = hashesMatched;
             return Collections.unmodifiableList(cachedTransactionHashes);
diff --git a/core/src/main/java/org/bitcoinj/core/FullPrunedBlockChain.java b/core/src/main/java/org/bitcoinj/core/FullPrunedBlockChain.java
index 4bdebbce2..d1f2810dd 100644
--- a/core/src/main/java/org/bitcoinj/core/FullPrunedBlockChain.java
+++ b/core/src/main/java/org/bitcoinj/core/FullPrunedBlockChain.java
@@ -217,14 +217,14 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
 
         blockStore.beginDatabaseBatchWrite();
 
-        LinkedList<UTXO> txOutsSpent = new LinkedList<UTXO>();
-        LinkedList<UTXO> txOutsCreated = new LinkedList<UTXO>();
+        LinkedList<UTXO> txOutsSpent = new LinkedList<>();
+        LinkedList<UTXO> txOutsCreated = new LinkedList<>();
         long sigOps = 0;
 
         if (scriptVerificationExecutor.isShutdown())
             scriptVerificationExecutor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
 
-        List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<Future<VerificationException>>(block.transactions.size());
+        List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<>(block.transactions.size());
         try {
             if (!params.isCheckpoint(height)) {
                 // BIP30 violator blocks are ones that contain a duplicated transaction. They are all in the
@@ -247,7 +247,7 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
                 boolean isCoinBase = tx.isCoinBase();
                 Coin valueIn = Coin.ZERO;
                 Coin valueOut = Coin.ZERO;
-                final List<Script> prevOutScripts = new LinkedList<Script>();
+                final List<Script> prevOutScripts = new LinkedList<>();
                 final Set<VerifyFlag> verifyFlags = params.getTransactionVerificationFlags(block, tx, getVersionTally(), height);
                 if (!isCoinBase) {
                     // For each input of the transaction remove the corresponding output from the set of unspent
@@ -308,7 +308,7 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
 
                 if (!isCoinBase && runScripts) {
                     // Because correctlySpends modifies transactions, this must come after we are done with tx
-                    FutureTask<VerificationException> future = new FutureTask<VerificationException>(new Verifier(tx, prevOutScripts, verifyFlags));
+                    FutureTask<VerificationException> future = new FutureTask<>(new Verifier(tx, prevOutScripts, verifyFlags));
                     scriptVerificationExecutor.execute(future);
                     listScriptVerificationResults.add(future);
                 }
@@ -361,8 +361,8 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
         try {
             List<Transaction> transactions = block.getTransactions();
             if (transactions != null) {
-                LinkedList<UTXO> txOutsSpent = new LinkedList<UTXO>();
-                LinkedList<UTXO> txOutsCreated = new LinkedList<UTXO>();
+                LinkedList<UTXO> txOutsSpent = new LinkedList<>();
+                LinkedList<UTXO> txOutsCreated = new LinkedList<>();
                 long sigOps = 0;
 
                 if (!params.isCheckpoint(newBlock.getHeight())) {
@@ -377,14 +377,14 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
 
                 if (scriptVerificationExecutor.isShutdown())
                     scriptVerificationExecutor = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
-                List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<Future<VerificationException>>(transactions.size());
+                List<Future<VerificationException>> listScriptVerificationResults = new ArrayList<>(transactions.size());
                 for (final Transaction tx : transactions) {
                     final Set<VerifyFlag> verifyFlags =
                         params.getTransactionVerificationFlags(newBlock.getHeader(), tx, getVersionTally(), Integer.SIZE);
                     boolean isCoinBase = tx.isCoinBase();
                     Coin valueIn = Coin.ZERO;
                     Coin valueOut = Coin.ZERO;
-                    final List<Script> prevOutScripts = new LinkedList<Script>();
+                    final List<Script> prevOutScripts = new LinkedList<>();
 
                     if (!isCoinBase) {
                         for (int index = 0; index < tx.getInputs().size(); index++) {
@@ -439,7 +439,7 @@ public class FullPrunedBlockChain extends AbstractBlockChain {
 
                     if (!isCoinBase) {
                         // Because correctlySpends modifies transactions, this must come after we are done with tx
-                        FutureTask<VerificationException> future = new FutureTask<VerificationException>(new Verifier(tx, prevOutScripts, verifyFlags));
+                        FutureTask<VerificationException> future = new FutureTask<>(new Verifier(tx, prevOutScripts, verifyFlags));
                         scriptVerificationExecutor.execute(future);
                         listScriptVerificationResults.add(future);
                     }
diff --git a/core/src/main/java/org/bitcoinj/core/GetBlocksMessage.java b/core/src/main/java/org/bitcoinj/core/GetBlocksMessage.java
index 4a1bcedb6..f13790d8e 100644
--- a/core/src/main/java/org/bitcoinj/core/GetBlocksMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/GetBlocksMessage.java
@@ -53,7 +53,7 @@ public class GetBlocksMessage extends Message {
         if (startCount > 500)
             throw new ProtocolException("Number of locators cannot be > 500, received: " + startCount);
         length = cursor - offset + ((startCount + 1) * 32);
-        locator = new ArrayList<Sha256Hash>(startCount);
+        locator = new ArrayList<>(startCount);
         for (int i = 0; i < startCount; i++) {
             locator.add(readHash());
         }
diff --git a/core/src/main/java/org/bitcoinj/core/HeadersMessage.java b/core/src/main/java/org/bitcoinj/core/HeadersMessage.java
index 0c899c8b0..cc3a749fe 100644
--- a/core/src/main/java/org/bitcoinj/core/HeadersMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/HeadersMessage.java
@@ -71,7 +71,7 @@ public class HeadersMessage extends Message {
             throw new ProtocolException("Too many headers: got " + numHeaders + " which is larger than " +
                                          MAX_HEADERS);
 
-        blockHeaders = new ArrayList<Block>();
+        blockHeaders = new ArrayList<>();
         final BitcoinSerializer serializer = this.params.getSerializer(true);
 
         for (int i = 0; i < numHeaders; ++i) {
diff --git a/core/src/main/java/org/bitcoinj/core/ListMessage.java b/core/src/main/java/org/bitcoinj/core/ListMessage.java
index 0a7dafe80..b0b8e3672 100644
--- a/core/src/main/java/org/bitcoinj/core/ListMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/ListMessage.java
@@ -47,7 +47,7 @@ public abstract class ListMessage extends Message {
 
     public ListMessage(NetworkParameters params) {
         super(params);
-        items = new ArrayList<InventoryItem>();
+        items = new ArrayList<>();
         length = 1; //length of 0 varint;
     }
 
@@ -77,7 +77,7 @@ public abstract class ListMessage extends Message {
         length = (int) (cursor - offset + (arrayLen * InventoryItem.MESSAGE_LENGTH));
 
         // An inv is vector<CInv> where CInv is int+hash. The int is either 1 or 2 for tx or block.
-        items = new ArrayList<InventoryItem>((int) arrayLen);
+        items = new ArrayList<>((int) arrayLen);
         for (int i = 0; i < arrayLen; i++) {
             if (cursor + InventoryItem.MESSAGE_LENGTH > payload.length) {
                 throw new ProtocolException("Ran off the end of the INV");
diff --git a/core/src/main/java/org/bitcoinj/core/NetworkParameters.java b/core/src/main/java/org/bitcoinj/core/NetworkParameters.java
index 2ce15ec97..6162c5a3e 100644
--- a/core/src/main/java/org/bitcoinj/core/NetworkParameters.java
+++ b/core/src/main/java/org/bitcoinj/core/NetworkParameters.java
@@ -104,7 +104,7 @@ public abstract class NetworkParameters {
     protected String[] dnsSeeds;
     protected int[] addrSeeds;
     protected HttpDiscovery.Details[] httpSeeds = {};
-    protected Map<Integer, Sha256Hash> checkpoints = new HashMap<Integer, Sha256Hash>();
+    protected Map<Integer, Sha256Hash> checkpoints = new HashMap<>();
     protected transient MessageSerializer defaultSerializer = null;
 
     protected NetworkParameters() {
diff --git a/core/src/main/java/org/bitcoinj/core/NotFoundMessage.java b/core/src/main/java/org/bitcoinj/core/NotFoundMessage.java
index bf9c77ae1..e5646bddc 100644
--- a/core/src/main/java/org/bitcoinj/core/NotFoundMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/NotFoundMessage.java
@@ -38,6 +38,6 @@ public class NotFoundMessage extends InventoryMessage {
 
     public NotFoundMessage(NetworkParameters params, List<InventoryItem> items) {
         super(params);
-        this.items = new ArrayList<InventoryItem>(items);
+        this.items = new ArrayList<>(items);
     }
 }
diff --git a/core/src/main/java/org/bitcoinj/core/PartialMerkleTree.java b/core/src/main/java/org/bitcoinj/core/PartialMerkleTree.java
index 832e1b75c..dbcae6cc5 100644
--- a/core/src/main/java/org/bitcoinj/core/PartialMerkleTree.java
+++ b/core/src/main/java/org/bitcoinj/core/PartialMerkleTree.java
@@ -89,8 +89,8 @@ public class PartialMerkleTree extends Message {
         int height = 0;
         while (getTreeWidth(allLeafHashes.size(), height) > 1)
             height++;
-        List<Boolean> bitList = new ArrayList<Boolean>();
-        List<Sha256Hash> hashes = new ArrayList<Sha256Hash>();
+        List<Boolean> bitList = new ArrayList<>();
+        List<Sha256Hash> hashes = new ArrayList<>();
         traverseAndBuild(height, 0, allLeafHashes, includeBits, bitList, hashes);
         byte[] bits = new byte[(int)Math.ceil(bitList.size() / 8.0)];
         for (int i = 0; i < bitList.size(); i++)
@@ -116,7 +116,7 @@ public class PartialMerkleTree extends Message {
         transactionCount = (int)readUint32();
 
         int nHashes = (int) readVarInt();
-        hashes = new ArrayList<Sha256Hash>(nHashes);
+        hashes = new ArrayList<>(nHashes);
         for (int i = 0; i < nHashes; i++)
             hashes.add(readHash());
 
diff --git a/core/src/main/java/org/bitcoinj/core/Peer.java b/core/src/main/java/org/bitcoinj/core/Peer.java
index 3b25ebabe..1728c48aa 100644
--- a/core/src/main/java/org/bitcoinj/core/Peer.java
+++ b/core/src/main/java/org/bitcoinj/core/Peer.java
@@ -65,19 +65,19 @@ public class Peer extends PeerSocketHandler {
     private final Context context;
 
     private final CopyOnWriteArrayList<ListenerRegistration<BlocksDownloadedEventListener>> blocksDownloadedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<BlocksDownloadedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<ChainDownloadStartedEventListener>> chainDownloadStartedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<ChainDownloadStartedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<PeerConnectedEventListener>> connectedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PeerConnectedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<PeerDisconnectedEventListener>> disconnectedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PeerDisconnectedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<GetDataEventListener>> getDataEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<GetDataEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<PreMessageReceivedEventListener>> preMessageReceivedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PreMessageReceivedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<OnTransactionBroadcastListener>> onTransactionEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<OnTransactionBroadcastListener>>();
+        = new CopyOnWriteArrayList<>();
     // Whether to try and download blocks and transactions from this peer. Set to false by PeerGroup if not the
     // primary peer. This is to avoid redundant work and concurrency problems with downloading the same chain
     // in parallel.
@@ -123,14 +123,14 @@ public class Peer extends PeerSocketHandler {
     //
     // It is important to avoid a nasty edge case where we can end up with parallel chain downloads proceeding
     // simultaneously if we were to receive a newly solved block whilst parts of the chain are streaming to us.
-    private final HashSet<Sha256Hash> pendingBlockDownloads = new HashSet<Sha256Hash>();
+    private final HashSet<Sha256Hash> pendingBlockDownloads = new HashSet<>();
     // Keep references to TransactionConfidence objects for transactions that were announced by a remote peer, but
     // which we haven't downloaded yet. These objects are de-duplicated by the TxConfidenceTable class.
     // Once the tx is downloaded (by some peer), the Transaction object that is created will have a reference to
     // the confidence object held inside it, and it's then up to the event listeners that receive the Transaction
     // to keep it pinned to the root set if they care about this data.
     @SuppressWarnings("MismatchedQueryAndUpdateOfCollection")
-    private final HashSet<TransactionConfidence> pendingTxDownloads = new HashSet<TransactionConfidence>();
+    private final HashSet<TransactionConfidence> pendingTxDownloads = new HashSet<>();
     // The lowest version number we're willing to accept. Lower than this will result in an immediate disconnect.
     private volatile int vMinProtocolVersion;
     // When an API user explicitly requests a block or transaction from a peer, the InventoryItem is put here
@@ -230,12 +230,12 @@ public class Peer extends PeerSocketHandler {
         this.vDownloadTxDependencyDepth = chain != null ? downloadTxDependencyDepth : 0;
         this.blockChain = chain;  // Allowed to be null.
         this.vDownloadData = chain != null;
-        this.getDataFutures = new CopyOnWriteArrayList<GetDataRequest>();
-        this.getAddrFutures = new LinkedList<SettableFuture<AddressMessage>>();
+        this.getDataFutures = new CopyOnWriteArrayList<>();
+        this.getAddrFutures = new LinkedList<>();
         this.fastCatchupTimeSecs = params.getGenesisBlock().getTimeSeconds();
-        this.pendingPings = new CopyOnWriteArrayList<PendingPing>();
+        this.pendingPings = new CopyOnWriteArrayList<>();
         this.vMinProtocolVersion = params.getProtocolVersionNum(NetworkParameters.ProtocolVersion.PONG);
-        this.wallets = new CopyOnWriteArrayList<Wallet>();
+        this.wallets = new CopyOnWriteArrayList<>();
         this.context = Context.get();
 
         this.versionHandshakeFuture.addListener(new Runnable() {
@@ -348,7 +348,7 @@ public class Peer extends PeerSocketHandler {
 
     /** Registers a listener that is called when messages are received. */
     public void addGetDataEventListener(Executor executor, GetDataEventListener listener) {
-        getDataEventListeners.add(new ListenerRegistration<GetDataEventListener>(listener, executor));
+        getDataEventListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /** Registers a listener that is called when a transaction is broadcast across the network */
@@ -358,7 +358,7 @@ public class Peer extends PeerSocketHandler {
 
     /** Registers a listener that is called when a transaction is broadcast across the network */
     public void addOnTransactionBroadcastListener(Executor executor, OnTransactionBroadcastListener listener) {
-        onTransactionEventListeners.add(new ListenerRegistration<OnTransactionBroadcastListener>(listener, executor));
+        onTransactionEventListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /** Registers a listener that is called immediately before a message is received */
@@ -368,7 +368,7 @@ public class Peer extends PeerSocketHandler {
 
     /** Registers a listener that is called immediately before a message is received */
     public void addPreMessageReceivedEventListener(Executor executor, PreMessageReceivedEventListener listener) {
-        preMessageReceivedEventListeners.add(new ListenerRegistration<PreMessageReceivedEventListener>(listener, executor));
+        preMessageReceivedEventListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     public boolean removeBlocksDownloadedEventListener(BlocksDownloadedEventListener listener) {
@@ -739,7 +739,7 @@ public class Peer extends PeerSocketHandler {
 
     protected void processGetData(GetDataMessage getdata) {
         log.info("{}: Received getdata message: {}", getAddress(), getdata.toString());
-        ArrayList<Message> items = new ArrayList<Message>();
+        ArrayList<Message> items = new ArrayList<>();
         for (ListenerRegistration<GetDataEventListener> registration : getDataEventListeners) {
             if (registration.executor != Threading.SAME_THREAD) continue;
             List<Message> listenerItems = registration.listener.getData(this, getdata);
@@ -868,7 +868,7 @@ public class Peer extends PeerSocketHandler {
         TransactionConfidence.ConfidenceType txConfidence = tx.getConfidence().getConfidenceType();
         Preconditions.checkArgument(txConfidence != TransactionConfidence.ConfidenceType.BUILDING);
         log.info("{}: Downloading dependencies of {}", getAddress(), tx.getHashAsString());
-        final LinkedList<Transaction> results = new LinkedList<Transaction>();
+        final LinkedList<Transaction> results = new LinkedList<>();
         // future will be invoked when the entire dependency tree has been walked and the results compiled.
         final ListenableFuture<Object> future = downloadDependenciesInternal(vDownloadTxDependencyDepth, 0, tx,
                 new Object(), results);
@@ -898,7 +898,7 @@ public class Peer extends PeerSocketHandler {
         // or depends on a no-fee transaction.
 
         // We may end up requesting transactions that we've already downloaded and thrown away here.
-        Set<Sha256Hash> needToRequest = new CopyOnWriteArraySet<Sha256Hash>();
+        Set<Sha256Hash> needToRequest = new CopyOnWriteArraySet<>();
         for (TransactionInput input : tx.getInputs()) {
             // There may be multiple inputs that connect to the same transaction.
             needToRequest.add(input.getOutpoint().getHash());
@@ -1081,7 +1081,7 @@ public class Peer extends PeerSocketHandler {
                     // that the new filter is now in use (which we have to simulate with a ping/pong), and then we can
                     // safely restart the chain download with the new filter that contains a new set of lookahead keys.
                     log.info("Bloom filter exhausted whilst processing block {}, discarding", m.getHash());
-                    awaitingFreshFilter = new LinkedList<Sha256Hash>();
+                    awaitingFreshFilter = new LinkedList<>();
                     awaitingFreshFilter.add(m.getHash());
                     awaitingFreshFilter.addAll(blockChain.drainOrphanBlocks());
                     return;   // Chain download process is restarted via a call to setBloomFilter.
@@ -1169,8 +1169,8 @@ public class Peer extends PeerSocketHandler {
         List<InventoryItem> items = inv.getItems();
 
         // Separate out the blocks and transactions, we'll handle them differently
-        List<InventoryItem> transactions = new LinkedList<InventoryItem>();
-        List<InventoryItem> blocks = new LinkedList<InventoryItem>();
+        List<InventoryItem> transactions = new LinkedList<>();
+        List<InventoryItem> blocks = new LinkedList<>();
 
         for (InventoryItem item : items) {
             switch (item.type) {
@@ -1427,7 +1427,7 @@ public class Peer extends PeerSocketHandler {
         // sends us the data we requested in a "headers" message.
 
         // TODO: Block locators should be abstracted out rather than special cased here.
-        List<Sha256Hash> blockLocator = new ArrayList<Sha256Hash>(51);
+        List<Sha256Hash> blockLocator = new ArrayList<>(51);
         // For now we don't do the exponential thinning as suggested here:
         //
         //   https://en.bitcoin.it/wiki/Protocol_specification#getblocks
@@ -1813,7 +1813,7 @@ public class Peer extends PeerSocketHandler {
             SettableFuture<UTXOsMessage> future = SettableFuture.create();
             // Add to the list of in flight requests.
             if (getutxoFutures == null)
-                getutxoFutures = new LinkedList<SettableFuture<UTXOsMessage>>();
+                getutxoFutures = new LinkedList<>();
             getutxoFutures.add(future);
             sendMessage(new GetUTXOsMessage(params, outPoints, includeMempool));
             return future;
diff --git a/core/src/main/java/org/bitcoinj/core/PeerGroup.java b/core/src/main/java/org/bitcoinj/core/PeerGroup.java
index 4f5dc2fd1..cac0d393d 100644
--- a/core/src/main/java/org/bitcoinj/core/PeerGroup.java
+++ b/core/src/main/java/org/bitcoinj/core/PeerGroup.java
@@ -115,25 +115,25 @@ public class PeerGroup implements TransactionBroadcaster {
     // Callback for events related to chain download.
     @Nullable @GuardedBy("lock") private PeerDataEventListener downloadListener;
     private final CopyOnWriteArrayList<ListenerRegistration<BlocksDownloadedEventListener>> peersBlocksDownloadedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<BlocksDownloadedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<ChainDownloadStartedEventListener>> peersChainDownloadStartedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<ChainDownloadStartedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     /** Callbacks for events related to peers connecting */
     protected final CopyOnWriteArrayList<ListenerRegistration<PeerConnectedEventListener>> peerConnectedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PeerConnectedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     /** Callbacks for events related to peer connection/disconnection */
     protected final CopyOnWriteArrayList<ListenerRegistration<PeerDiscoveredEventListener>> peerDiscoveredEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PeerDiscoveredEventListener>>();
+        = new CopyOnWriteArrayList<>();
     /** Callbacks for events related to peers disconnecting */
     protected final CopyOnWriteArrayList<ListenerRegistration<PeerDisconnectedEventListener>> peerDisconnectedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PeerDisconnectedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     /** Callbacks for events related to peer data being received */
     private final CopyOnWriteArrayList<ListenerRegistration<GetDataEventListener>> peerGetDataEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<GetDataEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<PreMessageReceivedEventListener>> peersPreMessageReceivedEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<PreMessageReceivedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     protected final CopyOnWriteArrayList<ListenerRegistration<OnTransactionBroadcastListener>> peersTransactionBroadastEventListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<OnTransactionBroadcastListener>>();
+        = new CopyOnWriteArrayList<>();
     // Peer discovery sources, will be polled occasionally if there aren't enough inactives.
     private final CopyOnWriteArraySet<PeerDiscovery> peerDiscoverers;
     // The version message to use for new connections.
@@ -323,8 +323,8 @@ public class PeerGroup implements TransactionBroadcaster {
         this.params = context.getParams();
         this.chain = chain;
         fastCatchupTimeSecs = params.getGenesisBlock().getTimeSeconds();
-        wallets = new CopyOnWriteArrayList<Wallet>();
-        peerFilterProviders = new CopyOnWriteArrayList<PeerFilterProvider>();
+        wallets = new CopyOnWriteArrayList<>();
+        peerFilterProviders = new CopyOnWriteArrayList<>();
 
         executor = createPrivateExecutor();
 
@@ -340,7 +340,7 @@ public class PeerGroup implements TransactionBroadcaster {
 
         downloadTxDependencyDepth = Integer.MAX_VALUE;
 
-        inactives = new PriorityQueue<PeerAddress>(1, new Comparator<PeerAddress>() {
+        inactives = new PriorityQueue<>(1, new Comparator<PeerAddress>() {
             @SuppressWarnings("FieldAccessNotGuarded")   // only called when inactives is accessed, and lock is held then.
             @Override
             public int compare(PeerAddress a, PeerAddress b) {
@@ -352,11 +352,11 @@ public class PeerGroup implements TransactionBroadcaster {
                 return result;
             }
         });
-        backoffMap = new HashMap<PeerAddress, ExponentialBackoff>();
-        peers = new CopyOnWriteArrayList<Peer>();
-        pendingPeers = new CopyOnWriteArrayList<Peer>();
+        backoffMap = new HashMap<>();
+        peers = new CopyOnWriteArrayList<>();
+        pendingPeers = new CopyOnWriteArrayList<>();
         channels = connectionManager;
-        peerDiscoverers = new CopyOnWriteArraySet<PeerDiscovery>();
+        peerDiscoverers = new CopyOnWriteArraySet<>();
         runningBroadcasts = Collections.synchronizedSet(new HashSet<TransactionBroadcast>());
         bloomFilterMerger = new FilterMerger(DEFAULT_BLOOM_FILTER_FP_RATE);
         vMinRequiredProtocolVersion = params.getProtocolVersionNum(NetworkParameters.ProtocolVersion.BLOOM_FILTER);
@@ -539,8 +539,8 @@ public class PeerGroup implements TransactionBroadcaster {
         // Runs on peer threads.
         lock.lock();
         try {
-            LinkedList<Message> transactions = new LinkedList<Message>();
-            LinkedList<InventoryItem> items = new LinkedList<InventoryItem>(m.getItems());
+            LinkedList<Message> transactions = new LinkedList<>();
+            LinkedList<InventoryItem> items = new LinkedList<>(m.getItems());
             Iterator<InventoryItem> it = items.iterator();
             while (it.hasNext()) {
                 InventoryItem item = it.next();
@@ -667,7 +667,7 @@ public class PeerGroup implements TransactionBroadcaster {
      * @see Peer#addBlocksDownloadedEventListener(Executor, BlocksDownloadedEventListener)
      */
     public void addBlocksDownloadedEventListener(Executor executor, BlocksDownloadedEventListener listener) {
-        peersBlocksDownloadedEventListeners.add(new ListenerRegistration<BlocksDownloadedEventListener>(checkNotNull(listener), executor));
+        peersBlocksDownloadedEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addBlocksDownloadedEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -684,7 +684,7 @@ public class PeerGroup implements TransactionBroadcaster {
      * chain download starts.</p>
      */
     public void addChainDownloadStartedEventListener(Executor executor, ChainDownloadStartedEventListener listener) {
-        peersChainDownloadStartedEventListeners.add(new ListenerRegistration<ChainDownloadStartedEventListener>(checkNotNull(listener), executor));
+        peersChainDownloadStartedEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addChainDownloadStartedEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -701,7 +701,7 @@ public class PeerGroup implements TransactionBroadcaster {
      * new peers are connected to.</p>
      */
     public void addConnectedEventListener(Executor executor, PeerConnectedEventListener listener) {
-        peerConnectedEventListeners.add(new ListenerRegistration<PeerConnectedEventListener>(checkNotNull(listener), executor));
+        peerConnectedEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addConnectedEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -718,7 +718,7 @@ public class PeerGroup implements TransactionBroadcaster {
      * peers are disconnected from.</p>
      */
     public void addDisconnectedEventListener(Executor executor, PeerDisconnectedEventListener listener) {
-        peerDisconnectedEventListeners.add(new ListenerRegistration<PeerDisconnectedEventListener>(checkNotNull(listener), executor));
+        peerDisconnectedEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addDisconnectedEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -735,7 +735,7 @@ public class PeerGroup implements TransactionBroadcaster {
      * peers are discovered.</p>
      */
     public void addDiscoveredEventListener(Executor executor, PeerDiscoveredEventListener listener) {
-        peerDiscoveredEventListeners.add(new ListenerRegistration<PeerDiscoveredEventListener>(checkNotNull(listener), executor));
+        peerDiscoveredEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
     }
 
     /** See {@link Peer#addGetDataEventListener(GetDataEventListener)} */
@@ -745,7 +745,7 @@ public class PeerGroup implements TransactionBroadcaster {
 
     /** See {@link Peer#addGetDataEventListener(Executor, GetDataEventListener)} */
     public void addGetDataEventListener(final Executor executor, final GetDataEventListener listener) {
-        peerGetDataEventListeners.add(new ListenerRegistration<GetDataEventListener>(checkNotNull(listener), executor));
+        peerGetDataEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addGetDataEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -759,7 +759,7 @@ public class PeerGroup implements TransactionBroadcaster {
 
     /** See {@link Peer#addOnTransactionBroadcastListener(OnTransactionBroadcastListener)} */
     public void addOnTransactionBroadcastListener(Executor executor, OnTransactionBroadcastListener listener) {
-        peersTransactionBroadastEventListeners.add(new ListenerRegistration<OnTransactionBroadcastListener>(checkNotNull(listener), executor));
+        peersTransactionBroadastEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addOnTransactionBroadcastListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -773,7 +773,7 @@ public class PeerGroup implements TransactionBroadcaster {
 
     /** See {@link Peer#addPreMessageReceivedEventListener(Executor, PreMessageReceivedEventListener)} */
     public void addPreMessageReceivedEventListener(Executor executor, PreMessageReceivedEventListener listener) {
-        peersPreMessageReceivedEventListeners.add(new ListenerRegistration<PreMessageReceivedEventListener>(checkNotNull(listener), executor));
+        peersPreMessageReceivedEventListeners.add(new ListenerRegistration<>(checkNotNull(listener), executor));
         for (Peer peer : getConnectedPeers())
             peer.addPreMessageReceivedEventListener(executor, listener);
         for (Peer peer : getPendingPeers())
@@ -873,7 +873,7 @@ public class PeerGroup implements TransactionBroadcaster {
     public List<Peer> getConnectedPeers() {
         lock.lock();
         try {
-            return new ArrayList<Peer>(peers);
+            return new ArrayList<>(peers);
         } finally {
             lock.unlock();
         }
@@ -885,7 +885,7 @@ public class PeerGroup implements TransactionBroadcaster {
     public List<Peer> getPendingPeers() {
         lock.lock();
         try {
-            return new ArrayList<Peer>(pendingPeers);
+            return new ArrayList<>(pendingPeers);
         } finally {
             lock.unlock();
         }
@@ -2179,7 +2179,7 @@ public class PeerGroup implements TransactionBroadcaster {
     public static int getMostCommonChainHeight(final List<Peer> peers) {
         if (peers.isEmpty())
             return 0;
-        List<Integer> heights = new ArrayList<Integer>(peers.size());
+        List<Integer> heights = new ArrayList<>(peers.size());
         for (Peer peer : peers) heights.add((int) peer.getBestHeight());
         return Utils.maxOfMostFreq(heights);
     }
@@ -2198,7 +2198,7 @@ public class PeerGroup implements TransactionBroadcaster {
             return null;
         // Make sure we don't select a peer that is behind/synchronizing itself.
         int mostCommonChainHeight = getMostCommonChainHeight(peers);
-        List<Peer> candidates = new ArrayList<Peer>();
+        List<Peer> candidates = new ArrayList<>();
         for (Peer peer : peers) {
             if (peer.getBestHeight() == mostCommonChainHeight) candidates.add(peer);
         }
@@ -2213,7 +2213,7 @@ public class PeerGroup implements TransactionBroadcaster {
             highestVersion = Math.max(peer.getPeerVersionMessage().clientVersion, highestVersion);
             preferredVersion = Math.min(highestVersion, PREFERRED_VERSION);
         }
-        ArrayList<Peer> candidates2 = new ArrayList<Peer>(candidates.size());
+        ArrayList<Peer> candidates2 = new ArrayList<>(candidates.size());
         for (Peer peer : candidates) {
             if (peer.getPeerVersionMessage().clientVersion >= preferredVersion) {
                 candidates2.add(peer);
diff --git a/core/src/main/java/org/bitcoinj/core/Transaction.java b/core/src/main/java/org/bitcoinj/core/Transaction.java
index 17a0ec153..dc4d03c2b 100644
--- a/core/src/main/java/org/bitcoinj/core/Transaction.java
+++ b/core/src/main/java/org/bitcoinj/core/Transaction.java
@@ -190,8 +190,8 @@ public class Transaction extends ChildMessage {
     public Transaction(NetworkParameters params) {
         super(params);
         version = 1;
-        inputs = new ArrayList<TransactionInput>();
-        outputs = new ArrayList<TransactionOutput>();
+        inputs = new ArrayList<>();
+        outputs = new ArrayList<>();
         // We don't initialize appearsIn deliberately as it's only useful for transactions stored in the wallet.
         length = 8; // 8 for std fields
     }
@@ -340,7 +340,7 @@ public class Transaction extends ChildMessage {
     public void addBlockAppearance(final Sha256Hash blockHash, int relativityOffset) {
         if (appearsInHashes == null) {
             // TODO: This could be a lot more memory efficient as we'll typically only store one element.
-            appearsInHashes = new TreeMap<Sha256Hash, Integer>();
+            appearsInHashes = new TreeMap<>();
         }
         appearsInHashes.put(blockHash, relativityOffset);
     }
@@ -553,7 +553,7 @@ public class Transaction extends ChildMessage {
         // First come the inputs.
         long numInputs = readVarInt();
         optimalEncodingMessageSize += VarInt.sizeOf(numInputs);
-        inputs = new ArrayList<TransactionInput>((int) numInputs);
+        inputs = new ArrayList<>((int) numInputs);
         for (long i = 0; i < numInputs; i++) {
             TransactionInput input = new TransactionInput(params, this, payload, cursor, serializer);
             inputs.add(input);
@@ -564,7 +564,7 @@ public class Transaction extends ChildMessage {
         // Now the outputs
         long numOutputs = readVarInt();
         optimalEncodingMessageSize += VarInt.sizeOf(numOutputs);
-        outputs = new ArrayList<TransactionOutput>((int) numOutputs);
+        outputs = new ArrayList<>((int) numOutputs);
         for (long i = 0; i < numOutputs; i++) {
             TransactionOutput output = new TransactionOutput(params, this, payload, cursor, serializer);
             outputs.add(output);
@@ -1039,7 +1039,7 @@ public class Transaction extends ChildMessage {
 
             if ((sigHashType & 0x1f) == SigHash.NONE.value) {
                 // SIGHASH_NONE means no outputs are signed at all - the signature is effectively for a "blank cheque".
-                tx.outputs = new ArrayList<TransactionOutput>(0);
+                tx.outputs = new ArrayList<>(0);
                 // The signature isn't broken by new versions of the transaction issued by other parties.
                 for (int i = 0; i < tx.inputs.size(); i++)
                     if (i != inputIndex)
@@ -1059,7 +1059,7 @@ public class Transaction extends ChildMessage {
                 }
                 // In SIGHASH_SINGLE the outputs after the matching input index are deleted, and the outputs before
                 // that position are "nulled out". Unintuitively, the value in a "null" transaction is set to -1.
-                tx.outputs = new ArrayList<TransactionOutput>(tx.outputs.subList(0, inputIndex + 1));
+                tx.outputs = new ArrayList<>(tx.outputs.subList(0, inputIndex + 1));
                 for (int i = 0; i < inputIndex; i++)
                     tx.outputs.set(i, new TransactionOutput(tx.params, tx, Coin.NEGATIVE_SATOSHI, new byte[] {}));
                 // The signature isn't broken by new versions of the transaction issued by other parties.
@@ -1162,7 +1162,7 @@ public class Transaction extends ChildMessage {
      * @return linked list of outputs relevant to the wallet in this transaction
      */
     public List<TransactionOutput> getWalletOutputs(TransactionBag transactionBag){
-        List<TransactionOutput> walletOutputs = new LinkedList<TransactionOutput>();
+        List<TransactionOutput> walletOutputs = new LinkedList<>();
         for (TransactionOutput o : outputs) {
             if (!o.isMineOrWatched(transactionBag)) continue;
             walletOutputs.add(o);
@@ -1288,7 +1288,7 @@ public class Transaction extends ChildMessage {
             throw new VerificationException.LargerThanMaxBlockSize();
 
         Coin valueOut = Coin.ZERO;
-        HashSet<TransactionOutPoint> outpoints = new HashSet<TransactionOutPoint>();
+        HashSet<TransactionOutPoint> outpoints = new HashSet<>();
         for (TransactionInput input : inputs) {
             if (outpoints.contains(input.getOutpoint()))
                 throw new VerificationException.DuplicatedOutPoint();
diff --git a/core/src/main/java/org/bitcoinj/core/TransactionConfidence.java b/core/src/main/java/org/bitcoinj/core/TransactionConfidence.java
index 6d0a7dec3..51dce88be 100644
--- a/core/src/main/java/org/bitcoinj/core/TransactionConfidence.java
+++ b/core/src/main/java/org/bitcoinj/core/TransactionConfidence.java
@@ -145,8 +145,8 @@ public class TransactionConfidence {
 
     public TransactionConfidence(Sha256Hash hash) {
         // Assume a default number of peers for our set.
-        broadcastBy = new CopyOnWriteArrayList<PeerAddress>();
-        listeners = new CopyOnWriteArrayList<ListenerRegistration<Listener>>();
+        broadcastBy = new CopyOnWriteArrayList<>();
+        listeners = new CopyOnWriteArrayList<>();
         this.hash = hash;
     }
 
@@ -206,7 +206,7 @@ public class TransactionConfidence {
      */
     public void addEventListener(Executor executor, Listener listener) {
         checkNotNull(listener);
-        listeners.addIfAbsent(new ListenerRegistration<Listener>(listener, executor));
+        listeners.addIfAbsent(new ListenerRegistration<>(listener, executor));
         pinnedConfidenceObjects.add(this);
     }
 
diff --git a/core/src/main/java/org/bitcoinj/core/TransactionInput.java b/core/src/main/java/org/bitcoinj/core/TransactionInput.java
index 790e8870b..b915b6dd3 100644
--- a/core/src/main/java/org/bitcoinj/core/TransactionInput.java
+++ b/core/src/main/java/org/bitcoinj/core/TransactionInput.java
@@ -165,14 +165,14 @@ public class TransactionInput extends ChildMessage {
         Script script = scriptSig == null ? null : scriptSig.get();
         if (script == null) {
             script = new Script(scriptBytes);
-            scriptSig = new WeakReference<Script>(script);
+            scriptSig = new WeakReference<>(script);
         }
         return script;
     }
 
     /** Set the given program as the scriptSig that is supposed to satisfy the connected output script. */
     public void setScriptSig(Script scriptSig) {
-        this.scriptSig = new WeakReference<Script>(checkNotNull(scriptSig));
+        this.scriptSig = new WeakReference<>(checkNotNull(scriptSig));
         // TODO: This should all be cleaned up so we have a consistent internal representation.
         setScriptBytes(scriptSig.getProgram());
     }
diff --git a/core/src/main/java/org/bitcoinj/core/TransactionOutputChanges.java b/core/src/main/java/org/bitcoinj/core/TransactionOutputChanges.java
index d006795ed..f17bc68b0 100644
--- a/core/src/main/java/org/bitcoinj/core/TransactionOutputChanges.java
+++ b/core/src/main/java/org/bitcoinj/core/TransactionOutputChanges.java
@@ -42,7 +42,7 @@ public class TransactionOutputChanges {
                              ((in.read() & 0xFF) << 8) |
                              ((in.read() & 0xFF) << 16) |
                              ((in.read() & 0xFF) << 24);
-        txOutsCreated = new LinkedList<UTXO>();
+        txOutsCreated = new LinkedList<>();
         for (int i = 0; i < numOutsCreated; i++)
             txOutsCreated.add(new UTXO(in));
         
@@ -50,7 +50,7 @@ public class TransactionOutputChanges {
                            ((in.read() & 0xFF) << 8) |
                            ((in.read() & 0xFF) << 16) |
                            ((in.read() & 0xFF) << 24);
-        txOutsSpent = new LinkedList<UTXO>();
+        txOutsSpent = new LinkedList<>();
         for (int i = 0; i < numOutsSpent; i++)
             txOutsSpent.add(new UTXO(in));
     }
diff --git a/core/src/main/java/org/bitcoinj/core/TxConfidenceTable.java b/core/src/main/java/org/bitcoinj/core/TxConfidenceTable.java
index cb2c4a3b3..e26d9faf2 100644
--- a/core/src/main/java/org/bitcoinj/core/TxConfidenceTable.java
+++ b/core/src/main/java/org/bitcoinj/core/TxConfidenceTable.java
@@ -72,7 +72,7 @@ public class TxConfidenceTable {
                 return size() > size;
             }
         };
-        referenceQueue = new ReferenceQueue<TransactionConfidence>();
+        referenceQueue = new ReferenceQueue<>();
     }
 
     /**
diff --git a/core/src/main/java/org/bitcoinj/core/UTXOsMessage.java b/core/src/main/java/org/bitcoinj/core/UTXOsMessage.java
index 6b04c42f1..f1192bdd8 100644
--- a/core/src/main/java/org/bitcoinj/core/UTXOsMessage.java
+++ b/core/src/main/java/org/bitcoinj/core/UTXOsMessage.java
@@ -67,7 +67,7 @@ public class UTXOsMessage extends Message {
             if (outputs.get(i) != null)
                 Utils.setBitLE(hits, i);
         }
-        this.outputs = new ArrayList<TransactionOutput>(outputs.size());
+        this.outputs = new ArrayList<>(outputs.size());
         for (TransactionOutput output : outputs) {
             if (output != null) this.outputs.add(output);
         }
@@ -111,7 +111,7 @@ public class UTXOsMessage extends Message {
         int numOuts = (int) readVarInt();
         if (numOuts < 0 || numOuts > InventoryMessage.MAX_INVENTORY_ITEMS)
             throw new ProtocolException("numOuts out of range: " + numOuts);
-        outputs = new ArrayList<TransactionOutput>(numOuts);
+        outputs = new ArrayList<>(numOuts);
         heights = new long[numOuts];
         for (int i = 0; i < numOuts; i++) {
             long version = readUint32();
@@ -135,7 +135,7 @@ public class UTXOsMessage extends Message {
 
     /** Returns the list of outputs that matched the query. */
     public List<TransactionOutput> getOutputs() {
-        return new ArrayList<TransactionOutput>(outputs);
+        return new ArrayList<>(outputs);
     }
 
     /** Returns the block heights of each output returned in getOutputs(), or MEMPOOL_HEIGHT if not confirmed yet. */
diff --git a/core/src/main/java/org/bitcoinj/core/Utils.java b/core/src/main/java/org/bitcoinj/core/Utils.java
index 80c2c7356..5094175bb 100644
--- a/core/src/main/java/org/bitcoinj/core/Utils.java
+++ b/core/src/main/java/org/bitcoinj/core/Utils.java
@@ -552,7 +552,7 @@ public class Utils {
     /** Enable or disable mock sleep.  If enabled, set mock time to current time. */
     public static void setMockSleep(boolean isEnable) {
         if (isEnable) {
-            mockSleepQueue = new ArrayBlockingQueue<Boolean>(1);
+            mockSleepQueue = new ArrayBlockingQueue<>(1);
             mockTime = new Date(System.currentTimeMillis());
         } else {
             mockSleepQueue = null;
@@ -589,7 +589,7 @@ public class Utils {
 
     public static int maxOfMostFreq(int... items) {
         // Java 6 sucks.
-        ArrayList<Integer> list = new ArrayList<Integer>(items.length);
+        ArrayList<Integer> list = new ArrayList<>(items.length);
         for (int item : items) list.add(item);
         return maxOfMostFreq(list);
     }
diff --git a/core/src/main/java/org/bitcoinj/crypto/HDUtils.java b/core/src/main/java/org/bitcoinj/crypto/HDUtils.java
index fb9581c9f..af7d2e52a 100644
--- a/core/src/main/java/org/bitcoinj/crypto/HDUtils.java
+++ b/core/src/main/java/org/bitcoinj/crypto/HDUtils.java
@@ -91,7 +91,7 @@ public final class HDUtils {
      */
     public static List<ChildNumber> parsePath(@Nonnull String path) {
         String[] parsedNodes = path.replace("M", "").split("/");
-        List<ChildNumber> nodes = new ArrayList<ChildNumber>();
+        List<ChildNumber> nodes = new ArrayList<>();
 
         for (String n : parsedNodes) {
             n = n.replaceAll(" ", "");
diff --git a/core/src/main/java/org/bitcoinj/crypto/MnemonicCode.java b/core/src/main/java/org/bitcoinj/crypto/MnemonicCode.java
index 8955517da..ce6d5db3d 100644
--- a/core/src/main/java/org/bitcoinj/crypto/MnemonicCode.java
+++ b/core/src/main/java/org/bitcoinj/crypto/MnemonicCode.java
@@ -87,7 +87,7 @@ public class MnemonicCode {
      */
     public MnemonicCode(InputStream wordstream, String wordListDigest) throws IOException, IllegalArgumentException {
         BufferedReader br = new BufferedReader(new InputStreamReader(wordstream, "UTF-8"));
-        this.wordList = new ArrayList<String>(2048);
+        this.wordList = new ArrayList<>(2048);
         MessageDigest md = Sha256Hash.newDigest();
         String word;
         while ((word = br.readLine()) != null) {
@@ -216,7 +216,7 @@ public class MnemonicCode {
         // which is a position in a wordlist.  We convert numbers into
         // words and use joined words as mnemonic sentence.
 
-        ArrayList<String> words = new ArrayList<String>();
+        ArrayList<String> words = new ArrayList<>();
         int nwords = concatBits.length / 11;
         for (int i = 0; i < nwords; ++i) {
             int index = 0;
diff --git a/core/src/main/java/org/bitcoinj/net/ConnectionHandler.java b/core/src/main/java/org/bitcoinj/net/ConnectionHandler.java
index 5a6b2c87e..d2afc1c75 100644
--- a/core/src/main/java/org/bitcoinj/net/ConnectionHandler.java
+++ b/core/src/main/java/org/bitcoinj/net/ConnectionHandler.java
@@ -61,7 +61,7 @@ class ConnectionHandler implements MessageWriteTarget {
     @GuardedBy("lock") private boolean closeCalled = false;
 
     @GuardedBy("lock") private long bytesToWriteRemaining = 0;
-    @GuardedBy("lock") private final LinkedList<ByteBuffer> bytesToWrite = new LinkedList<ByteBuffer>();
+    @GuardedBy("lock") private final LinkedList<ByteBuffer> bytesToWrite = new LinkedList<>();
 
     private Set<ConnectionHandler> connectedHandlers;
 
diff --git a/core/src/main/java/org/bitcoinj/net/NioClientManager.java b/core/src/main/java/org/bitcoinj/net/NioClientManager.java
index f1cc249b4..fe585430e 100644
--- a/core/src/main/java/org/bitcoinj/net/NioClientManager.java
+++ b/core/src/main/java/org/bitcoinj/net/NioClientManager.java
@@ -46,7 +46,7 @@ public class NioClientManager extends AbstractExecutionThreadService implements
 
         PendingConnect(SocketChannel sc, StreamConnection connection, SocketAddress address) { this.sc = sc; this.connection = connection; this.address = address; }
     }
-    final Queue<PendingConnect> newConnectionChannels = new LinkedBlockingQueue<PendingConnect>();
+    final Queue<PendingConnect> newConnectionChannels = new LinkedBlockingQueue<>();
 
     // Added to/removed from by the individual ConnectionHandler's, thus must by synchronized on its own.
     private final Set<ConnectionHandler> connectedHandlers = Collections.synchronizedSet(new HashSet<ConnectionHandler>());
diff --git a/core/src/main/java/org/bitcoinj/net/ProtobufConnection.java b/core/src/main/java/org/bitcoinj/net/ProtobufConnection.java
index dec49870e..d87de8c90 100644
--- a/core/src/main/java/org/bitcoinj/net/ProtobufConnection.java
+++ b/core/src/main/java/org/bitcoinj/net/ProtobufConnection.java
@@ -77,7 +77,7 @@ public class ProtobufConnection<MessageType extends MessageLite> extends Abstrac
     @GuardedBy("lock") private byte[] messageBytes;
     private final ReentrantLock lock = Threading.lock("ProtobufConnection");
 
-    @VisibleForTesting final AtomicReference<MessageWriteTarget> writeTarget = new AtomicReference<MessageWriteTarget>();
+    @VisibleForTesting final AtomicReference<MessageWriteTarget> writeTarget = new AtomicReference<>();
 
     /**
      * Creates a new protobuf handler.
diff --git a/core/src/main/java/org/bitcoinj/net/discovery/DnsDiscovery.java b/core/src/main/java/org/bitcoinj/net/discovery/DnsDiscovery.java
index 1d05a8379..154927737 100644
--- a/core/src/main/java/org/bitcoinj/net/discovery/DnsDiscovery.java
+++ b/core/src/main/java/org/bitcoinj/net/discovery/DnsDiscovery.java
@@ -56,7 +56,7 @@ public class DnsDiscovery extends MultiplexingDiscovery {
     }
 
     private static List<PeerDiscovery> buildDiscoveries(NetworkParameters params, String[] seeds) {
-        List<PeerDiscovery> discoveries = new ArrayList<PeerDiscovery>();
+        List<PeerDiscovery> discoveries = new ArrayList<>();
         if (seeds != null)
             for (String seed : seeds)
                 discoveries.add(new DnsSeedDiscovery(params, seed));
diff --git a/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelClientState.java b/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelClientState.java
index 8054efc01..a91d36e2b 100644
--- a/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelClientState.java
+++ b/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelClientState.java
@@ -103,7 +103,7 @@ public abstract class PaymentChannelClientState {
     protected StoredClientChannel storedChannel;
 
     PaymentChannelClientState(StoredClientChannel storedClientChannel, Wallet wallet) throws VerificationException {
-        this.stateMachine = new StateMachine<State>(State.UNINITIALISED, getStateTransitions());
+        this.stateMachine = new StateMachine<>(State.UNINITIALISED, getStateTransitions());
         this.wallet = checkNotNull(wallet);
         this.myKey = checkNotNull(storedClientChannel.myKey);
         this.serverKey = checkNotNull(storedClientChannel.serverKey);
@@ -140,7 +140,7 @@ public abstract class PaymentChannelClientState {
      */
     public PaymentChannelClientState(Wallet wallet, ECKey myKey, ECKey serverKey,
                                      Coin value, long expiryTimeInSeconds) throws VerificationException {
-        this.stateMachine = new StateMachine<State>(State.UNINITIALISED, getStateTransitions());
+        this.stateMachine = new StateMachine<>(State.UNINITIALISED, getStateTransitions());
         this.wallet = checkNotNull(wallet);
         this.serverKey = checkNotNull(serverKey);
         this.myKey = checkNotNull(myKey);
diff --git a/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelServerState.java b/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelServerState.java
index f69783a09..871a7f0ef 100644
--- a/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelServerState.java
+++ b/core/src/main/java/org/bitcoinj/protocols/channels/PaymentChannelServerState.java
@@ -117,7 +117,7 @@ public abstract class PaymentChannelServerState {
 
     PaymentChannelServerState(StoredServerChannel storedServerChannel, Wallet wallet, TransactionBroadcaster broadcaster) throws VerificationException {
         synchronized (storedServerChannel) {
-            this.stateMachine = new StateMachine<State>(State.UNINITIALISED, getStateTransitions());
+            this.stateMachine = new StateMachine<>(State.UNINITIALISED, getStateTransitions());
             this.wallet = checkNotNull(wallet);
             this.broadcaster = checkNotNull(broadcaster);
             this.contract = checkNotNull(storedServerChannel.contract);
@@ -141,7 +141,7 @@ public abstract class PaymentChannelServerState {
      * @param minExpireTime The earliest time at which the client can claim the refund transaction (UNIX timestamp of block)
      */
     public PaymentChannelServerState(TransactionBroadcaster broadcaster, Wallet wallet, ECKey serverKey, long minExpireTime) {
-        this.stateMachine = new StateMachine<State>(State.UNINITIALISED, getStateTransitions());
+        this.stateMachine = new StateMachine<>(State.UNINITIALISED, getStateTransitions());
         this.serverKey = checkNotNull(serverKey);
         this.wallet = checkNotNull(wallet);
         this.broadcaster = checkNotNull(broadcaster);
diff --git a/core/src/main/java/org/bitcoinj/protocols/channels/StoredPaymentChannelServerStates.java b/core/src/main/java/org/bitcoinj/protocols/channels/StoredPaymentChannelServerStates.java
index 72e4f34fa..c80e971dc 100644
--- a/core/src/main/java/org/bitcoinj/protocols/channels/StoredPaymentChannelServerStates.java
+++ b/core/src/main/java/org/bitcoinj/protocols/channels/StoredPaymentChannelServerStates.java
@@ -47,7 +47,7 @@ public class StoredPaymentChannelServerStates implements WalletExtension {
     static final String EXTENSION_ID = StoredPaymentChannelServerStates.class.getName();
     static final int MAX_SECONDS_TO_WAIT_FOR_BROADCASTER_TO_BE_SET = 10;
 
-    @GuardedBy("lock") @VisibleForTesting final Map<Sha256Hash, StoredServerChannel> mapChannels = new HashMap<Sha256Hash, StoredServerChannel>();
+    @GuardedBy("lock") @VisibleForTesting final Map<Sha256Hash, StoredServerChannel> mapChannels = new HashMap<>();
     private Wallet wallet;
     private final SettableFuture<TransactionBroadcaster> broadcasterFuture = SettableFuture.create();
 
diff --git a/core/src/main/java/org/bitcoinj/protocols/payments/PaymentProtocol.java b/core/src/main/java/org/bitcoinj/protocols/payments/PaymentProtocol.java
index 3a77baf70..e440269c5 100644
--- a/core/src/main/java/org/bitcoinj/protocols/payments/PaymentProtocol.java
+++ b/core/src/main/java/org/bitcoinj/protocols/payments/PaymentProtocol.java
@@ -340,7 +340,7 @@ public class PaymentProtocol {
      */
     public static List<Transaction> parseTransactionsFromPaymentMessage(NetworkParameters params,
             Protos.Payment paymentMessage) {
-        final List<Transaction> transactions = new ArrayList<Transaction>(paymentMessage.getTransactionsCount());
+        final List<Transaction> transactions = new ArrayList<>(paymentMessage.getTransactionsCount());
         for (final ByteString transaction : paymentMessage.getTransactionsList())
             transactions.add(params.getDefaultSerializer().makeTransaction(transaction.toByteArray()));
         return transactions;
diff --git a/core/src/main/java/org/bitcoinj/protocols/payments/PaymentSession.java b/core/src/main/java/org/bitcoinj/protocols/payments/PaymentSession.java
index 1d916c180..5e25047af 100644
--- a/core/src/main/java/org/bitcoinj/protocols/payments/PaymentSession.java
+++ b/core/src/main/java/org/bitcoinj/protocols/payments/PaymentSession.java
@@ -224,7 +224,7 @@ public class PaymentSession {
      * Returns the outputs of the payment request.
      */
     public List<PaymentProtocol.Output> getOutputs() {
-        List<PaymentProtocol.Output> outputs = new ArrayList<PaymentProtocol.Output>(paymentDetails.getOutputsCount());
+        List<PaymentProtocol.Output> outputs = new ArrayList<>(paymentDetails.getOutputsCount());
         for (Protos.Output output : paymentDetails.getOutputsList()) {
             Coin amount = output.hasAmount() ? Coin.valueOf(output.getAmount()) : null;
             outputs.add(new PaymentProtocol.Output(amount, output.getScript().toByteArray()));
diff --git a/core/src/main/java/org/bitcoinj/script/Script.java b/core/src/main/java/org/bitcoinj/script/Script.java
index 9ddb45ca7..6adbeeffb 100644
--- a/core/src/main/java/org/bitcoinj/script/Script.java
+++ b/core/src/main/java/org/bitcoinj/script/Script.java
@@ -101,7 +101,7 @@ public class Script {
 
     // Used from ScriptBuilder.
     Script(List<ScriptChunk> chunks) {
-        this.chunks = Collections.unmodifiableList(new ArrayList<ScriptChunk>(chunks));
+        this.chunks = Collections.unmodifiableList(new ArrayList<>(chunks));
         creationTimeSeconds = Utils.currentTimeSeconds();
     }
 
@@ -177,7 +177,7 @@ public class Script {
      * Bitcoin Core does something similar.</p>
      */
     private void parse(byte[] program) throws ScriptException {
-        chunks = new ArrayList<ScriptChunk>(5);   // Common size.
+        chunks = new ArrayList<>(5);   // Common size.
         ByteArrayInputStream bis = new ByteArrayInputStream(program);
         int initialSize = bis.available();
         while (bis.available() > 0) {
@@ -864,8 +864,8 @@ public class Script {
         int opCount = 0;
         int lastCodeSepLocation = 0;
         
-        LinkedList<byte[]> altstack = new LinkedList<byte[]>();
-        LinkedList<Boolean> ifStack = new LinkedList<Boolean>();
+        LinkedList<byte[]> altstack = new LinkedList<>();
+        LinkedList<Boolean> ifStack = new LinkedList<>();
         
         for (ScriptChunk chunk : script.chunks) {
             boolean shouldExecute = !ifStack.contains(false);
@@ -1487,7 +1487,7 @@ public class Script {
         if (stack.size() < pubKeyCount + 1)
             throw new ScriptException("Attempted OP_CHECKMULTISIG(VERIFY) on a stack with size < num_of_pubkeys + 2");
 
-        LinkedList<byte[]> pubkeys = new LinkedList<byte[]>();
+        LinkedList<byte[]> pubkeys = new LinkedList<>();
         for (int i = 0; i < pubKeyCount; i++) {
             byte[] pubKey = stack.pollLast();
             pubkeys.add(pubKey);
@@ -1499,7 +1499,7 @@ public class Script {
         if (stack.size() < sigCount + 1)
             throw new ScriptException("Attempted OP_CHECKMULTISIG(VERIFY) on a stack with size < num_of_pubkeys + num_of_signatures + 3");
 
-        LinkedList<byte[]> sigs = new LinkedList<byte[]>();
+        LinkedList<byte[]> sigs = new LinkedList<>();
         for (int i = 0; i < sigCount; i++) {
             byte[] sig = stack.pollLast();
             sigs.add(sig);
@@ -1591,12 +1591,12 @@ public class Script {
         if (getProgram().length > 10000 || scriptPubKey.getProgram().length > 10000)
             throw new ScriptException("Script larger than 10,000 bytes");
         
-        LinkedList<byte[]> stack = new LinkedList<byte[]>();
+        LinkedList<byte[]> stack = new LinkedList<>();
         LinkedList<byte[]> p2shStack = null;
         
         executeScript(txContainingThis, scriptSigIndex, this, stack, verifyFlags);
         if (verifyFlags.contains(VerifyFlag.P2SH))
-            p2shStack = new LinkedList<byte[]>(stack);
+            p2shStack = new LinkedList<>(stack);
         executeScript(txContainingThis, scriptSigIndex, scriptPubKey, stack, verifyFlags);
         
         if (stack.size() == 0)
diff --git a/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java b/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
index c6bece728..ea800c338 100644
--- a/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
+++ b/core/src/main/java/org/bitcoinj/script/ScriptBuilder.java
@@ -49,7 +49,7 @@ public class ScriptBuilder {
 
     /** Creates a fresh ScriptBuilder with the given program as the starting point. */
     public ScriptBuilder(Script template) {
-        chunks = new ArrayList<ScriptChunk>(template.getChunks());
+        chunks = new ArrayList<>(template.getChunks());
     }
 
     /** Adds the given chunk to the end of the program */
@@ -178,7 +178,7 @@ public class ScriptBuilder {
         if (num == 0) {
             data = new byte[0];
         } else {
-            Stack<Byte> result = new Stack<Byte>();
+            Stack<Byte> result = new Stack<>();
             final boolean neg = num < 0;
             long absvalue = Math.abs(num);
 
@@ -276,7 +276,7 @@ public class ScriptBuilder {
 
     /** Create a program that satisfies an OP_CHECKMULTISIG program. */
     public static Script createMultiSigInputScript(List<TransactionSignature> signatures) {
-        List<byte[]> sigs = new ArrayList<byte[]>(signatures.size());
+        List<byte[]> sigs = new ArrayList<>(signatures.size());
         for (TransactionSignature signature : signatures) {
             sigs.add(signature.encodeToBitcoin());
         }
@@ -300,7 +300,7 @@ public class ScriptBuilder {
      */
     public static Script createP2SHMultiSigInputScript(@Nullable List<TransactionSignature> signatures,
                                                        Script multisigProgram) {
-        List<byte[]> sigs = new ArrayList<byte[]>();
+        List<byte[]> sigs = new ArrayList<>();
         if (signatures == null) {
             // create correct number of empty signatures
             int numSigs = multisigProgram.getNumberOfSignaturesRequiredToSpend();
@@ -422,7 +422,7 @@ public class ScriptBuilder {
      * redeem script in the lexicographical sorting order.
      */
     public static Script createRedeemScript(int threshold, List<ECKey> pubkeys) {
-        pubkeys = new ArrayList<ECKey>(pubkeys);
+        pubkeys = new ArrayList<>(pubkeys);
         Collections.sort(pubkeys, ECKey.PUBKEY_COMPARATOR);
         return ScriptBuilder.createMultiSigOutputScript(threshold, pubkeys);
     }
diff --git a/core/src/main/java/org/bitcoinj/signers/TransactionSigner.java b/core/src/main/java/org/bitcoinj/signers/TransactionSigner.java
index e149bf10a..9eccaf715 100644
--- a/core/src/main/java/org/bitcoinj/signers/TransactionSigner.java
+++ b/core/src/main/java/org/bitcoinj/signers/TransactionSigner.java
@@ -54,7 +54,7 @@ public interface TransactionSigner {
 
         public ProposedTransaction(Transaction partialTx) {
             this.partialTx = partialTx;
-            this.keyPaths = new HashMap<Script, List<ChildNumber>>();
+            this.keyPaths = new HashMap<>();
         }
     }
 
diff --git a/core/src/main/java/org/bitcoinj/store/DatabaseFullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/DatabaseFullPrunedBlockStore.java
index 5c977c117..6a2f1376a 100644
--- a/core/src/main/java/org/bitcoinj/store/DatabaseFullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/DatabaseFullPrunedBlockStore.java
@@ -168,8 +168,8 @@ public abstract class DatabaseFullPrunedBlockStore implements FullPrunedBlockSto
         this.schemaName = schemaName;
         this.username = username;
         this.password = password;
-        this.conn = new ThreadLocal<Connection>();
-        this.allConnections = new LinkedList<Connection>();
+        this.conn = new ThreadLocal<>();
+        this.allConnections = new LinkedList<>();
 
         try {
             Class.forName(getDatabaseDriverClass());
@@ -246,7 +246,7 @@ public abstract class DatabaseFullPrunedBlockStore implements FullPrunedBlockSto
      * @return The SQL prepared statements.
      */
     protected List<String> getCompatibilitySQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(SELECT_COMPATIBILITY_COINBASE_SQL);
         return sqlStatements;
     }
@@ -264,7 +264,7 @@ public abstract class DatabaseFullPrunedBlockStore implements FullPrunedBlockSto
      * @return The SQL drop statements.
      */
     protected List<String> getDropTablesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(DROP_SETTINGS_TABLE);
         sqlStatements.add(DROP_HEADERS_TABLE);
         sqlStatements.add(DROP_UNDOABLE_TABLE);
@@ -810,7 +810,7 @@ public abstract class DatabaseFullPrunedBlockStore implements FullPrunedBlockSto
                         ((transactions[offset++] & 0xFF) << 8) |
                         ((transactions[offset++] & 0xFF) << 16) |
                         ((transactions[offset++] & 0xFF) << 24);
-                List<Transaction> transactionList = new LinkedList<Transaction>();
+                List<Transaction> transactionList = new LinkedList<>();
                 for (int i = 0; i < numTxn; i++) {
                     Transaction tx = params.getDefaultSerializer().makeTransaction(transactions, offset);
                     transactionList.add(tx);
@@ -1158,7 +1158,7 @@ public abstract class DatabaseFullPrunedBlockStore implements FullPrunedBlockSto
     @Override
     public List<UTXO> getOpenTransactionOutputs(List<Address> addresses) throws UTXOProviderException {
         PreparedStatement s = null;
-        List<UTXO> outputs = new ArrayList<UTXO>();
+        List<UTXO> outputs = new ArrayList<>();
         try {
             maybeConnect();
             s = conn.get().prepareStatement(getTransactionOutputSelectSQL());
diff --git a/core/src/main/java/org/bitcoinj/store/H2FullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/H2FullPrunedBlockStore.java
index f5eda873a..5a2453795 100644
--- a/core/src/main/java/org/bitcoinj/store/H2FullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/H2FullPrunedBlockStore.java
@@ -133,7 +133,7 @@ public class H2FullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateTablesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_SETTINGS_TABLE);
         sqlStatements.add(CREATE_HEADERS_TABLE);
         sqlStatements.add(CREATE_UNDOABLE_TABLE);
@@ -143,7 +143,7 @@ public class H2FullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateIndexesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_UNDOABLE_TABLE_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESS_MULTI_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESSTARGETABLE_INDEX);
diff --git a/core/src/main/java/org/bitcoinj/store/LevelDBFullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/LevelDBFullPrunedBlockStore.java
index 443c52a91..a1df8e4dc 100644
--- a/core/src/main/java/org/bitcoinj/store/LevelDBFullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/LevelDBFullPrunedBlockStore.java
@@ -259,9 +259,9 @@ public class LevelDBFullPrunedBlockStore implements FullPrunedBlockStore {
         fullStoreDepth = blockCount;
         this.instrument = instrument;
         this.exitBlock = exitBlock;
-        methodStartTime = new HashMap<String, Stopwatch>();
-        methodCalls = new HashMap<String, Long>();
-        methodTotalTime = new HashMap<String, Long>();
+        methodStartTime = new HashMap<>();
+        methodCalls = new HashMap<>();
+        methodTotalTime = new HashMap<>();
 
         this.filename = filename;
         this.leveldbReadCache = leveldbReadCache;
@@ -424,7 +424,7 @@ public class LevelDBFullPrunedBlockStore implements FullPrunedBlockStore {
         // This is critical or if one address paid another could get incorrect
         // results
 
-        List<UTXO> results = new LinkedList<UTXO>();
+        List<UTXO> results = new LinkedList<>();
         for (Address a : addresses) {
             ByteBuffer bb = ByteBuffer.allocate(21);
             bb.put((byte) KeyType.ADDRESS_HASHINDEX.ordinal());
@@ -674,7 +674,7 @@ public class LevelDBFullPrunedBlockStore implements FullPrunedBlockStore {
                 int offset = 0;
                 int numTxn = ((transactions[offset++] & 0xFF) << 0) | ((transactions[offset++] & 0xFF) << 8)
                         | ((transactions[offset++] & 0xFF) << 16) | ((transactions[offset++] & 0xFF) << 24);
-                List<Transaction> transactionList = new LinkedList<Transaction>();
+                List<Transaction> transactionList = new LinkedList<>();
                 for (int i = 0; i < numTxn; i++) {
                     Transaction tx = new Transaction(params, transactions, offset);
                     transactionList.add(tx);
@@ -1039,10 +1039,10 @@ public class LevelDBFullPrunedBlockStore implements FullPrunedBlockStore {
             beginMethod("beginDatabaseBatchWrite");
 
         batch = db.createWriteBatch();
-        uncommited = new HashMap<ByteBuffer, byte[]>();
-        uncommitedDeletes = new HashSet<ByteBuffer>();
-        utxoUncommittedCache = new HashMap<ByteBuffer, UTXO>();
-        utxoUncommittedDeletedCache = new HashSet<ByteBuffer>();
+        uncommited = new HashMap<>();
+        uncommitedDeletes = new HashSet<>();
+        utxoUncommittedCache = new HashMap<>();
+        utxoUncommittedDeletedCache = new HashSet<>();
         autoCommit = false;
         if (instrument)
             endMethod("beginDatabaseBatchWrite");
diff --git a/core/src/main/java/org/bitcoinj/store/MemoryFullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/MemoryFullPrunedBlockStore.java
index b07fe892f..8954bb681 100644
--- a/core/src/main/java/org/bitcoinj/store/MemoryFullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/MemoryFullPrunedBlockStore.java
@@ -90,10 +90,10 @@ class TransactionalHashMap<KeyType, ValueType> {
     HashMap<KeyType, ValueType> map;
     
     public TransactionalHashMap() {
-        tempMap = new ThreadLocal<HashMap<KeyType, ValueType>>();
-        tempSetRemoved = new ThreadLocal<HashSet<KeyType>>();
-        inTransaction = new ThreadLocal<Boolean>();
-        map = new HashMap<KeyType, ValueType>();
+        tempMap = new ThreadLocal<>();
+        tempSetRemoved = new ThreadLocal<>();
+        inTransaction = new ThreadLocal<>();
+        map = new HashMap<>();
     }
     
     public void beginDatabaseBatchWrite() {
@@ -131,7 +131,7 @@ class TransactionalHashMap<KeyType, ValueType> {
     }
 
     public List<ValueType> values() {
-        List<ValueType> valueTypes = new ArrayList<ValueType>();
+        List<ValueType> valueTypes = new ArrayList<>();
         for (KeyType keyType : map.keySet()) {
             valueTypes.add(get(keyType));
         }
@@ -182,8 +182,8 @@ class TransactionalMultiKeyHashMap<UniqueKeyType, MultiKeyType, ValueType> {
     HashMap<MultiKeyType, Set<UniqueKeyType>> mapKeys;
     
     public TransactionalMultiKeyHashMap() {
-        mapValues = new TransactionalHashMap<UniqueKeyType, ValueType>();
-        mapKeys = new HashMap<MultiKeyType, Set<UniqueKeyType>>();
+        mapValues = new TransactionalHashMap<>();
+        mapKeys = new HashMap<>();
     }
     
     public void BeginTransaction() {
@@ -207,7 +207,7 @@ class TransactionalMultiKeyHashMap<UniqueKeyType, MultiKeyType, ValueType> {
         mapValues.put(uniqueKey, value);
         Set<UniqueKeyType> set = mapKeys.get(multiKey);
         if (set == null) {
-            set = new HashSet<UniqueKeyType>();
+            set = new HashSet<>();
             set.add(uniqueKey);
             mapKeys.put(multiKey, set);
         }else{
@@ -253,9 +253,9 @@ public class MemoryFullPrunedBlockStore implements FullPrunedBlockStore {
      * @param fullStoreDepth The depth of blocks to keep FullStoredBlocks instead of StoredBlocks
      */
     public MemoryFullPrunedBlockStore(NetworkParameters params, int fullStoreDepth) {
-        blockMap = new TransactionalHashMap<Sha256Hash, StoredBlockAndWasUndoableFlag>();
-        fullBlockMap = new TransactionalMultiKeyHashMap<Sha256Hash, Integer, StoredUndoableBlock>();
-        transactionOutputMap = new TransactionalHashMap<StoredTransactionOutPoint, UTXO>();
+        blockMap = new TransactionalHashMap<>();
+        fullBlockMap = new TransactionalMultiKeyHashMap<>();
+        transactionOutputMap = new TransactionalHashMap<>();
         this.fullStoreDepth = fullStoreDepth > 0 ? fullStoreDepth : 1;
         // Insert the genesis block.
         try {
@@ -415,7 +415,7 @@ public class MemoryFullPrunedBlockStore implements FullPrunedBlockStore {
     public List<UTXO> getOpenTransactionOutputs(List<Address> addresses) throws UTXOProviderException {
         // This is *NOT* optimal: We go through all the outputs and select the ones we are looking for.
         // If someone uses this store for production then they have a lot more to worry about than an inefficient impl :)
-        List<UTXO> foundOutputs = new ArrayList<UTXO>();
+        List<UTXO> foundOutputs = new ArrayList<>();
         List<UTXO> outputsList = transactionOutputMap.values();
         for (UTXO output : outputsList) {
             for (Address address : addresses) {
diff --git a/core/src/main/java/org/bitcoinj/store/MySQLFullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/MySQLFullPrunedBlockStore.java
index 2d6bda198..ca5d454f5 100644
--- a/core/src/main/java/org/bitcoinj/store/MySQLFullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/MySQLFullPrunedBlockStore.java
@@ -125,7 +125,7 @@ public class MySQLFullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateTablesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_SETTINGS_TABLE);
         sqlStatements.add(CREATE_HEADERS_TABLE);
         sqlStatements.add(CREATE_UNDOABLE_TABLE);
@@ -135,7 +135,7 @@ public class MySQLFullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateIndexesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_UNDOABLE_TABLE_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESS_MULTI_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESSTARGETABLE_INDEX);
diff --git a/core/src/main/java/org/bitcoinj/store/PostgresFullPrunedBlockStore.java b/core/src/main/java/org/bitcoinj/store/PostgresFullPrunedBlockStore.java
index a08283bfc..2f3ad9d90 100644
--- a/core/src/main/java/org/bitcoinj/store/PostgresFullPrunedBlockStore.java
+++ b/core/src/main/java/org/bitcoinj/store/PostgresFullPrunedBlockStore.java
@@ -133,7 +133,7 @@ public class PostgresFullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateTablesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_SETTINGS_TABLE);
         sqlStatements.add(CREATE_HEADERS_TABLE);
         sqlStatements.add(CREATE_UNDOABLE_TABLE);
@@ -143,7 +143,7 @@ public class PostgresFullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateIndexesSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add(CREATE_UNDOABLE_TABLE_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESS_MULTI_INDEX);
         sqlStatements.add(CREATE_OUTPUTS_ADDRESSTARGETABLE_INDEX);
@@ -154,7 +154,7 @@ public class PostgresFullPrunedBlockStore extends DatabaseFullPrunedBlockStore {
 
     @Override
     protected List<String> getCreateSchemeSQL() {
-        List<String> sqlStatements = new ArrayList<String>();
+        List<String> sqlStatements = new ArrayList<>();
         sqlStatements.add("CREATE SCHEMA IF NOT EXISTS " + schemaName);
         sqlStatements.add("set search_path to '" + schemaName +"'");
         return sqlStatements;
diff --git a/core/src/main/java/org/bitcoinj/uri/BitcoinURI.java b/core/src/main/java/org/bitcoinj/uri/BitcoinURI.java
index a4502c676..6b2f7eea7 100644
--- a/core/src/main/java/org/bitcoinj/uri/BitcoinURI.java
+++ b/core/src/main/java/org/bitcoinj/uri/BitcoinURI.java
@@ -98,7 +98,7 @@ public class BitcoinURI {
     /**
      * Contains all the parameters in the order in which they were processed
      */
-    private final Map<String, Object> parameterMap = new LinkedHashMap<String, Object>();
+    private final Map<String, Object> parameterMap = new LinkedHashMap<>();
 
     /**
      * Constructs a new BitcoinURI from the given string. Can be for any network.
@@ -299,7 +299,7 @@ public class BitcoinURI {
      * all subsequent URLs are fallbacks.
      */
     public List<String> getPaymentRequestUrls() {
-        ArrayList<String> urls = new ArrayList<String>();
+        ArrayList<String> urls = new ArrayList<>();
         while (true) {
             int i = urls.size();
             String paramName = FIELD_PAYMENT_REQUEST_URL + (i > 0 ? Integer.toString(i) : "");
diff --git a/core/src/main/java/org/bitcoinj/utils/BaseTaggableObject.java b/core/src/main/java/org/bitcoinj/utils/BaseTaggableObject.java
index 9d8b5f8d2..a87b106d2 100644
--- a/core/src/main/java/org/bitcoinj/utils/BaseTaggableObject.java
+++ b/core/src/main/java/org/bitcoinj/utils/BaseTaggableObject.java
@@ -57,7 +57,7 @@ public class BaseTaggableObject implements TaggableObject {
         checkNotNull(tag);
         checkNotNull(value);
         if (tags == null)
-            tags = new HashMap<String, ByteString>();
+            tags = new HashMap<>();
         tags.put(tag, value);
     }
 
diff --git a/core/src/main/java/org/bitcoinj/utils/BlockFileLoader.java b/core/src/main/java/org/bitcoinj/utils/BlockFileLoader.java
index 77869e796..4f0b0400a 100644
--- a/core/src/main/java/org/bitcoinj/utils/BlockFileLoader.java
+++ b/core/src/main/java/org/bitcoinj/utils/BlockFileLoader.java
@@ -61,7 +61,7 @@ public class BlockFileLoader implements Iterable<Block>, Iterator<Block> {
             defaultDataDir = System.getProperty("user.home") + "/.bitcoin/blocks/";
         }
         
-        List<File> list = new LinkedList<File>();
+        List<File> list = new LinkedList<>();
         for (int i = 0; true; i++) {
             File file = new File(defaultDataDir + String.format(Locale.US, "blk%05d.dat", i));
             if (!file.exists())
diff --git a/core/src/main/java/org/bitcoinj/utils/BtcFormat.java b/core/src/main/java/org/bitcoinj/utils/BtcFormat.java
index a8d2bbfdf..dd72be0f6 100644
--- a/core/src/main/java/org/bitcoinj/utils/BtcFormat.java
+++ b/core/src/main/java/org/bitcoinj/utils/BtcFormat.java
@@ -923,7 +923,7 @@ public abstract class BtcFormat extends Format {
     public static BtcFormat getCoinInstance() { return getCoinInstance(defaultLocale()); }
 
     private static List<Integer> boxAsList(int[] elements) throws IllegalArgumentException {
-        List<Integer> list = new ArrayList<Integer>(elements.length);
+        List<Integer> list = new ArrayList<>(elements.length);
         for (int e : elements) {
             checkArgument(e > 0, "Size of decimal group must be at least one.");
             list.add(e);
diff --git a/core/src/main/java/org/bitcoinj/utils/MonetaryFormat.java b/core/src/main/java/org/bitcoinj/utils/MonetaryFormat.java
index 60297ab86..122eca19b 100644
--- a/core/src/main/java/org/bitcoinj/utils/MonetaryFormat.java
+++ b/core/src/main/java/org/bitcoinj/utils/MonetaryFormat.java
@@ -157,7 +157,7 @@ public final class MonetaryFormat {
      *            any number numbers of decimals, one for each group
      */
     public MonetaryFormat optionalDecimals(int... groups) {
-        List<Integer> decimalGroups = new ArrayList<Integer>(groups.length);
+        List<Integer> decimalGroups = new ArrayList<>(groups.length);
         for (int group : groups)
             decimalGroups.add(group);
         return new MonetaryFormat(negativeSign, positiveSign, zeroDigit, decimalMark, minDecimals, decimalGroups,
@@ -183,7 +183,7 @@ public final class MonetaryFormat {
      */
     public MonetaryFormat repeatOptionalDecimals(int decimals, int repetitions) {
         checkArgument(repetitions >= 0);
-        List<Integer> decimalGroups = new ArrayList<Integer>(repetitions);
+        List<Integer> decimalGroups = new ArrayList<>(repetitions);
         for (int i = 0; i < repetitions; i++)
             decimalGroups.add(decimals);
         return new MonetaryFormat(negativeSign, positiveSign, zeroDigit, decimalMark, minDecimals, decimalGroups,
diff --git a/core/src/main/java/org/bitcoinj/utils/Threading.java b/core/src/main/java/org/bitcoinj/utils/Threading.java
index bbbdbdfd9..db76d7326 100644
--- a/core/src/main/java/org/bitcoinj/utils/Threading.java
+++ b/core/src/main/java/org/bitcoinj/utils/Threading.java
@@ -95,7 +95,7 @@ public class Threading {
         public UserThread() {
             super("bitcoinj user thread");
             setDaemon(true);
-            tasks = new LinkedBlockingQueue<Runnable>();
+            tasks = new LinkedBlockingQueue<>();
             start();
         }
 
diff --git a/core/src/main/java/org/bitcoinj/utils/VersionTally.java b/core/src/main/java/org/bitcoinj/utils/VersionTally.java
index 5e37bbc3f..1985264a5 100644
--- a/core/src/main/java/org/bitcoinj/utils/VersionTally.java
+++ b/core/src/main/java/org/bitcoinj/utils/VersionTally.java
@@ -99,7 +99,7 @@ public class VersionTally {
     public void initialize(final BlockStore blockStore, final StoredBlock chainHead)
         throws BlockStoreException {
         StoredBlock versionBlock = chainHead;
-        final Stack<Long> versions = new Stack<Long>();
+        final Stack<Long> versions = new Stack<>();
 
         // We don't know how many blocks back we can go, so load what we can first
         versions.push(versionBlock.getHeader().getVersion());
diff --git a/core/src/main/java/org/bitcoinj/wallet/BasicKeyChain.java b/core/src/main/java/org/bitcoinj/wallet/BasicKeyChain.java
index 04b0990f0..00690a9c1 100644
--- a/core/src/main/java/org/bitcoinj/wallet/BasicKeyChain.java
+++ b/core/src/main/java/org/bitcoinj/wallet/BasicKeyChain.java
@@ -58,9 +58,9 @@ public class BasicKeyChain implements EncryptableKeyChain {
 
     public BasicKeyChain(@Nullable KeyCrypter crypter) {
         this.keyCrypter = crypter;
-        hashToKeys = new LinkedHashMap<ByteString, ECKey>();
-        pubkeyToKeys = new LinkedHashMap<ByteString, ECKey>();
-        listeners = new CopyOnWriteArrayList<ListenerRegistration<KeyChainEventListener>>();
+        hashToKeys = new LinkedHashMap<>();
+        pubkeyToKeys = new LinkedHashMap<>();
+        listeners = new CopyOnWriteArrayList<>();
     }
 
     /** Returns the {@link KeyCrypter} in use or null if the key chain is not encrypted. */
@@ -99,7 +99,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
             if (hashToKeys.size() < numberOfKeys) {
                 checkState(keyCrypter == null);
 
-                List<ECKey> keys = new ArrayList<ECKey>();
+                List<ECKey> keys = new ArrayList<>();
                 for (int i = 0; i < numberOfKeys - hashToKeys.size(); i++) {
                     keys.add(new ECKey());
                 }
@@ -109,7 +109,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
                 queueOnKeysAdded(immutableKeys);
             }
 
-            List<ECKey> keysToReturn = new ArrayList<ECKey>();
+            List<ECKey> keysToReturn = new ArrayList<>();
             int count = 0;
             while (hashToKeys.values().iterator().hasNext() && numberOfKeys != count) {
                 keysToReturn.add(hashToKeys.values().iterator().next());
@@ -125,7 +125,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
     public List<ECKey> getKeys() {
         lock.lock();
         try {
-            return new ArrayList<ECKey>(hashToKeys.values());
+            return new ArrayList<>(hashToKeys.values());
         } finally {
             lock.unlock();
         }
@@ -145,7 +145,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
             for (ECKey key : keys) {
                 checkKeyEncryptionStateMatches(key);
             }
-            List<ECKey> actuallyAdded = new ArrayList<ECKey>(keys.size());
+            List<ECKey> actuallyAdded = new ArrayList<>(keys.size());
             for (final ECKey key : keys) {
                 if (hasKey(key)) continue;
                 actuallyAdded.add(key);
@@ -284,7 +284,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
     }
 
     public List<ListenerRegistration<KeyChainEventListener>> getListeners() {
-        return new ArrayList<ListenerRegistration<KeyChainEventListener>>(listeners);
+        return new ArrayList<>(listeners);
     }
 
     ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
@@ -294,7 +294,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
     ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////
 
     Map<ECKey, Protos.Key.Builder> serializeToEditableProtobufs() {
-        Map<ECKey, Protos.Key.Builder> result = new LinkedHashMap<ECKey, Protos.Key.Builder>();
+        Map<ECKey, Protos.Key.Builder> result = new LinkedHashMap<>();
         for (ECKey ecKey : hashToKeys.values()) {
             Protos.Key.Builder protoKey = serializeEncryptableItem(ecKey);
             protoKey.setPublicKey(ByteString.copyFrom(ecKey.getPubKey()));
@@ -306,7 +306,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
     @Override
     public List<Protos.Key> serializeToProtobuf() {
         Collection<Protos.Key.Builder> builders = serializeToEditableProtobufs().values();
-        List<Protos.Key> result = new ArrayList<Protos.Key>(builders.size());
+        List<Protos.Key> result = new ArrayList<>(builders.size());
         for (Protos.Key.Builder builder : builders) result.add(builder.build());
         return result;
     }
@@ -407,7 +407,7 @@ public class BasicKeyChain implements EncryptableKeyChain {
 
     @Override
     public void addEventListener(KeyChainEventListener listener, Executor executor) {
-        listeners.add(new ListenerRegistration<KeyChainEventListener>(listener, executor));
+        listeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     @Override
diff --git a/core/src/main/java/org/bitcoinj/wallet/DecryptingKeyBag.java b/core/src/main/java/org/bitcoinj/wallet/DecryptingKeyBag.java
index b9f1e46f7..d997f031e 100644
--- a/core/src/main/java/org/bitcoinj/wallet/DecryptingKeyBag.java
+++ b/core/src/main/java/org/bitcoinj/wallet/DecryptingKeyBag.java
@@ -54,7 +54,7 @@ public class DecryptingKeyBag implements KeyBag {
     }
 
     private RedeemData maybeDecrypt(RedeemData redeemData) {
-        List<ECKey> decryptedKeys = new ArrayList<ECKey>();
+        List<ECKey> decryptedKeys = new ArrayList<>();
         for (ECKey key : redeemData.keys) {
             decryptedKeys.add(maybeDecrypt(key));
         }
diff --git a/core/src/main/java/org/bitcoinj/wallet/DefaultCoinSelector.java b/core/src/main/java/org/bitcoinj/wallet/DefaultCoinSelector.java
index 4d6349c52..55ea53c23 100644
--- a/core/src/main/java/org/bitcoinj/wallet/DefaultCoinSelector.java
+++ b/core/src/main/java/org/bitcoinj/wallet/DefaultCoinSelector.java
@@ -34,10 +34,10 @@ import java.util.*;
 public class DefaultCoinSelector implements CoinSelector {
     @Override
     public CoinSelection select(Coin target, List<TransactionOutput> candidates) {
-        ArrayList<TransactionOutput> selected = new ArrayList<TransactionOutput>();
+        ArrayList<TransactionOutput> selected = new ArrayList<>();
         // Sort the inputs by age*value so we get the highest "coindays" spent.
         // TODO: Consider changing the wallets internal format to track just outputs and keep them ordered.
-        ArrayList<TransactionOutput> sortedOutputs = new ArrayList<TransactionOutput>(candidates);
+        ArrayList<TransactionOutput> sortedOutputs = new ArrayList<>(candidates);
         // When calculating the wallet balance, we may be asked to select all possible coins, if so, avoid sorting
         // them in order to improve performance.
         // TODO: Take in network parameters when instanatiated, and then test against the current network. Or just have a boolean parameter for "give me everything"
diff --git a/core/src/main/java/org/bitcoinj/wallet/DeterministicKeyChain.java b/core/src/main/java/org/bitcoinj/wallet/DeterministicKeyChain.java
index 835b46600..b484e5bb6 100644
--- a/core/src/main/java/org/bitcoinj/wallet/DeterministicKeyChain.java
+++ b/core/src/main/java/org/bitcoinj/wallet/DeterministicKeyChain.java
@@ -489,7 +489,7 @@ public class DeterministicKeyChain implements EncryptableKeyChain {
             // and calculate the full lookahead zone there, so network requests will always use the right amount.
             List<DeterministicKey> lookahead = maybeLookAhead(parentKey, index, 0, 0);
             basicKeyChain.importKeys(lookahead);
-            List<DeterministicKey> keys = new ArrayList<DeterministicKey>(numberOfKeys);
+            List<DeterministicKey> keys = new ArrayList<>(numberOfKeys);
             for (int i = 0; i < numberOfKeys; i++) {
                 ImmutableList<ChildNumber> path = HDUtils.append(parentKey.getPath(), new ChildNumber(index - numberOfKeys + i, false));
                 DeterministicKey k = hierarchy.get(path, false, false);
@@ -1153,12 +1153,12 @@ public class DeterministicKeyChain implements EncryptableKeyChain {
         final int needed = issued + lookaheadSize + lookaheadThreshold - numChildren;
 
         if (needed <= lookaheadThreshold)
-            return new ArrayList<DeterministicKey>();
+            return new ArrayList<>();
 
         log.info("{} keys needed for {} = {} issued + {} lookahead size + {} lookahead threshold - {} num children",
                 needed, parent.getPathAsString(), issued, lookaheadSize, lookaheadThreshold, numChildren);
 
-        List<DeterministicKey> result  = new ArrayList<DeterministicKey>(needed);
+        List<DeterministicKey> result  = new ArrayList<>(needed);
         final Stopwatch watch = Stopwatch.createStarted();
         int nextChild = numChildren;
         for (int i = 0; i < needed; i++) {
@@ -1219,7 +1219,7 @@ public class DeterministicKeyChain implements EncryptableKeyChain {
         List<ECKey> keys = basicKeyChain.getKeys();
         if (!includeLookahead) {
             int treeSize = internalParentKey.getPath().size();
-            List<ECKey> issuedKeys = new LinkedList<ECKey>();
+            List<ECKey> issuedKeys = new LinkedList<>();
             for (ECKey key : keys) {
                 DeterministicKey detkey = (DeterministicKey) key;
                 DeterministicKey parent = detkey.getParent();
@@ -1238,7 +1238,7 @@ public class DeterministicKeyChain implements EncryptableKeyChain {
      * Returns only the external keys that have been issued by this chain, lookahead not included.
      */
     public List<ECKey> getIssuedReceiveKeys() {
-        final List<ECKey> keys = new ArrayList<ECKey>(getKeys(false, false));
+        final List<ECKey> keys = new ArrayList<>(getKeys(false, false));
         for (Iterator<ECKey> i = keys.iterator(); i.hasNext();) {
             DeterministicKey parent = ((DeterministicKey) i.next()).getParent();
             if (parent == null || !externalParentKey.equals(parent))
diff --git a/core/src/main/java/org/bitcoinj/wallet/FilteringCoinSelector.java b/core/src/main/java/org/bitcoinj/wallet/FilteringCoinSelector.java
index fb142dbee..10d15f8c1 100644
--- a/core/src/main/java/org/bitcoinj/wallet/FilteringCoinSelector.java
+++ b/core/src/main/java/org/bitcoinj/wallet/FilteringCoinSelector.java
@@ -27,7 +27,7 @@ import java.util.List;
  */
 public class FilteringCoinSelector implements CoinSelector {
     protected CoinSelector delegate;
-    protected HashSet<TransactionOutPoint> spent = new HashSet<TransactionOutPoint>();
+    protected HashSet<TransactionOutPoint> spent = new HashSet<>();
 
     public FilteringCoinSelector(CoinSelector delegate) {
         this.delegate = delegate;
diff --git a/core/src/main/java/org/bitcoinj/wallet/KeyChainGroup.java b/core/src/main/java/org/bitcoinj/wallet/KeyChainGroup.java
index 6aba8d79d..7afd6d73c 100644
--- a/core/src/main/java/org/bitcoinj/wallet/KeyChainGroup.java
+++ b/core/src/main/java/org/bitcoinj/wallet/KeyChainGroup.java
@@ -97,12 +97,12 @@ public class KeyChainGroup implements KeyBag {
                           @Nullable EnumMap<KeyChain.KeyPurpose, DeterministicKey> currentKeys, @Nullable KeyCrypter crypter) {
         this.params = params;
         this.basic = basicKeyChain == null ? new BasicKeyChain() : basicKeyChain;
-        this.chains = new LinkedList<DeterministicKeyChain>(checkNotNull(chains));
+        this.chains = new LinkedList<>(checkNotNull(chains));
         this.keyCrypter = crypter;
         this.currentKeys = currentKeys == null
                 ? new EnumMap<KeyChain.KeyPurpose, DeterministicKey>(KeyChain.KeyPurpose.class)
                 : currentKeys;
-        this.currentAddresses = new EnumMap<KeyChain.KeyPurpose, Address>(KeyChain.KeyPurpose.class);
+        this.currentAddresses = new EnumMap<>(KeyChain.KeyPurpose.class);
         maybeLookaheadScripts();
 
         if (isMarried()) {
@@ -491,7 +491,7 @@ public class KeyChainGroup implements KeyBag {
         checkNotNull(aesKey);
         // This code must be exception safe.
         BasicKeyChain newBasic = basic.toEncrypted(keyCrypter, aesKey);
-        List<DeterministicKeyChain> newChains = new ArrayList<DeterministicKeyChain>(chains.size());
+        List<DeterministicKeyChain> newChains = new ArrayList<>(chains.size());
         if (chains.isEmpty() && basic.numKeys() == 0) {
             // No HD chains and no random keys: encrypting an entirely empty keychain group. But we can't do that, we
             // must have something to encrypt: so instantiate a new HD chain here.
@@ -515,7 +515,7 @@ public class KeyChainGroup implements KeyBag {
         // This code must be exception safe.
         checkNotNull(aesKey);
         BasicKeyChain newBasic = basic.toDecrypted(aesKey);
-        List<DeterministicKeyChain> newChains = new ArrayList<DeterministicKeyChain>(chains.size());
+        List<DeterministicKeyChain> newChains = new ArrayList<>(chains.size());
         for (DeterministicKeyChain chain : chains)
             newChains.add(chain.toDecrypted(aesKey));
 
@@ -746,7 +746,7 @@ public class KeyChainGroup implements KeyBag {
     private static EnumMap<KeyChain.KeyPurpose, DeterministicKey> createCurrentKeysMap(List<DeterministicKeyChain> chains) {
         DeterministicKeyChain activeChain = chains.get(chains.size() - 1);
 
-        EnumMap<KeyChain.KeyPurpose, DeterministicKey> currentKeys = new EnumMap<KeyChain.KeyPurpose, DeterministicKey>(KeyChain.KeyPurpose.class);
+        EnumMap<KeyChain.KeyPurpose, DeterministicKey> currentKeys = new EnumMap<>(KeyChain.KeyPurpose.class);
 
         // assuming that only RECEIVE and CHANGE keys are being used at the moment, we will treat latest issued external key
         // as current RECEIVE key and latest issued internal key as CHANGE key. This should be changed as soon as other
@@ -801,7 +801,7 @@ public class KeyChainGroup implements KeyBag {
 
     /** Returns a copy of the current list of chains. */
     public List<DeterministicKeyChain> getDeterministicKeyChains() {
-        return new ArrayList<DeterministicKeyChain>(chains);
+        return new ArrayList<>(chains);
     }
     /**
      * Returns a counter that increases (by an arbitrary amount) each time new keys have been calculated due to
diff --git a/core/src/main/java/org/bitcoinj/wallet/MarriedKeyChain.java b/core/src/main/java/org/bitcoinj/wallet/MarriedKeyChain.java
index 5990cb1b2..b74bd6b3b 100644
--- a/core/src/main/java/org/bitcoinj/wallet/MarriedKeyChain.java
+++ b/core/src/main/java/org/bitcoinj/wallet/MarriedKeyChain.java
@@ -57,7 +57,7 @@ import static com.google.common.collect.Lists.newArrayList;
 public class MarriedKeyChain extends DeterministicKeyChain {
     // The map holds P2SH redeem script and corresponding ECKeys issued by this KeyChainGroup (including lookahead)
     // mapped to redeem script hashes.
-    private LinkedHashMap<ByteString, RedeemData> marriedKeysRedeemData = new LinkedHashMap<ByteString, RedeemData>();
+    private LinkedHashMap<ByteString, RedeemData> marriedKeysRedeemData = new LinkedHashMap<>();
 
     private List<DeterministicKeyChain> followingKeyChains;
 
diff --git a/core/src/main/java/org/bitcoinj/wallet/RedeemData.java b/core/src/main/java/org/bitcoinj/wallet/RedeemData.java
index 2f8e8cc11..162667ec0 100644
--- a/core/src/main/java/org/bitcoinj/wallet/RedeemData.java
+++ b/core/src/main/java/org/bitcoinj/wallet/RedeemData.java
@@ -39,7 +39,7 @@ public class RedeemData {
 
     private RedeemData(List<ECKey> keys, Script redeemScript) {
         this.redeemScript = redeemScript;
-        List<ECKey> sortedKeys = new ArrayList<ECKey>(keys);
+        List<ECKey> sortedKeys = new ArrayList<>(keys);
         Collections.sort(sortedKeys, ECKey.PUBKEY_COMPARATOR);
         this.keys = sortedKeys;
     }
diff --git a/core/src/main/java/org/bitcoinj/wallet/Wallet.java b/core/src/main/java/org/bitcoinj/wallet/Wallet.java
index d666b9df2..f5c64aa4a 100644
--- a/core/src/main/java/org/bitcoinj/wallet/Wallet.java
+++ b/core/src/main/java/org/bitcoinj/wallet/Wallet.java
@@ -192,17 +192,17 @@ public class Wallet extends BaseTaggableObject
     private long lastBlockSeenTimeSecs;
 
     private final CopyOnWriteArrayList<ListenerRegistration<WalletChangeEventListener>> changeListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<WalletChangeEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<WalletCoinsReceivedEventListener>> coinsReceivedListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<WalletCoinsReceivedEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<WalletCoinsSentEventListener>> coinsSentListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<WalletCoinsSentEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<WalletReorganizeEventListener>> reorganizeListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<WalletReorganizeEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<ScriptsChangeEventListener>> scriptChangeListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<ScriptsChangeEventListener>>();
+        = new CopyOnWriteArrayList<>();
     private final CopyOnWriteArrayList<ListenerRegistration<TransactionConfidenceEventListener>> transactionConfidenceListeners
-        = new CopyOnWriteArrayList<ListenerRegistration<TransactionConfidenceEventListener>>();
+        = new CopyOnWriteArrayList<>();
 
     // A listener that relays confidence changes from the transaction confidence object to the wallet event listener,
     // as a convenience to API users so they don't have to register on every transaction themselves.
@@ -319,21 +319,21 @@ public class Wallet extends BaseTaggableObject
         if (this.keyChainGroup.numKeys() == 0)
             this.keyChainGroup.createAndActivateNewHDChain();
         watchedScripts = Sets.newHashSet();
-        unspent = new HashMap<Sha256Hash, Transaction>();
-        spent = new HashMap<Sha256Hash, Transaction>();
-        pending = new HashMap<Sha256Hash, Transaction>();
-        dead = new HashMap<Sha256Hash, Transaction>();
-        transactions = new HashMap<Sha256Hash, Transaction>();
-        extensions = new HashMap<String, WalletExtension>();
+        unspent = new HashMap<>();
+        spent = new HashMap<>();
+        pending = new HashMap<>();
+        dead = new HashMap<>();
+        transactions = new HashMap<>();
+        extensions = new HashMap<>();
         // Use a linked hash map to ensure ordering of event listeners is correct.
-        confidenceChanged = new LinkedHashMap<Transaction, TransactionConfidence.Listener.ChangeReason>();
-        signers = new ArrayList<TransactionSigner>();
+        confidenceChanged = new LinkedHashMap<>();
+        signers = new ArrayList<>();
         addTransactionSigner(new LocalTransactionSigner());
         createTransientState();
     }
 
     private void createTransientState() {
-        ignoreNextNewBlock = new HashSet<Sha256Hash>();
+        ignoreNextNewBlock = new HashSet<>();
         txConfidenceListener = new TransactionConfidence.Listener() {
             @Override
             public void onConfidenceChanged(TransactionConfidence confidence, TransactionConfidence.Listener.ChangeReason reason) {
@@ -532,7 +532,7 @@ public class Wallet extends BaseTaggableObject
      */
     public List<Address> getIssuedReceiveAddresses() {
         final List<ECKey> keys = getIssuedReceiveKeys();
-        List<Address> addresses = new ArrayList<Address>(keys.size());
+        List<Address> addresses = new ArrayList<>(keys.size());
         for (ECKey key : keys)
             addresses.add(key.toAddress(getParams()));
         return addresses;
@@ -593,7 +593,7 @@ public class Wallet extends BaseTaggableObject
     public List<Script> getWatchedScripts() {
         keyChainGroupLock.lock();
         try {
-            return new ArrayList<Script>(watchedScripts);
+            return new ArrayList<>(watchedScripts);
         } finally {
             keyChainGroupLock.unlock();
         }
@@ -961,7 +961,7 @@ public class Wallet extends BaseTaggableObject
     public List<Address> getWatchedAddresses() {
         keyChainGroupLock.lock();
         try {
-            List<Address> addresses = new LinkedList<Address>();
+            List<Address> addresses = new LinkedList<>();
             for (Script script : watchedScripts)
                 if (script.isSentToAddress())
                     addresses.add(script.getToAddress(params));
@@ -1546,7 +1546,7 @@ public class Wallet extends BaseTaggableObject
         try {
             Set<Transaction> transactions = getTransactions(true);
 
-            Set<Sha256Hash> hashes = new HashSet<Sha256Hash>();
+            Set<Sha256Hash> hashes = new HashSet<>();
             for (Transaction tx : transactions) {
                 hashes.add(tx.getHash());
             }
@@ -1813,7 +1813,7 @@ public class Wallet extends BaseTaggableObject
         checkState(lock.isHeldByCurrentThread());
         if (tx.isCoinBase()) return Sets.newHashSet();
         // Compile a set of outpoints that are spent by tx.
-        HashSet<TransactionOutPoint> outpoints = new HashSet<TransactionOutPoint>();
+        HashSet<TransactionOutPoint> outpoints = new HashSet<>();
         for (TransactionInput input : tx.getInputs()) {
             outpoints.add(input.getOutpoint());
         }
@@ -1838,7 +1838,7 @@ public class Wallet extends BaseTaggableObject
      * and all txns spending the outputs of those txns, recursively.
      */
     void addTransactionsDependingOn(Set<Transaction> txSet, Set<Transaction> txPool) {
-        Map<Sha256Hash, Transaction> txQueue = new LinkedHashMap<Sha256Hash, Transaction>();
+        Map<Sha256Hash, Transaction> txQueue = new LinkedHashMap<>();
         for (Transaction tx : txSet) {
             txQueue.put(tx.getHash(), tx);
         }
@@ -2053,7 +2053,7 @@ public class Wallet extends BaseTaggableObject
      * as there is no guarantee on the order of the returned txns besides what was already stated.
      */
     List<Transaction> sortTxnsByDependency(Set<Transaction> inputSet) {
-        ArrayList<Transaction> result = new ArrayList<Transaction>(inputSet);
+        ArrayList<Transaction> result = new ArrayList<>(inputSet);
         for (int i = 0; i < result.size()-1; i++) {
             boolean txAtISpendsOtherTxInTheList;
             do {
@@ -2315,7 +2315,7 @@ public class Wallet extends BaseTaggableObject
 
     // Updates the wallet when a double spend occurs. overridingTx can be null for the case of coinbases
     private void killTxns(Set<Transaction> txnsToKill, @Nullable Transaction overridingTx) {
-        LinkedList<Transaction> work = new LinkedList<Transaction>(txnsToKill);
+        LinkedList<Transaction> work = new LinkedList<>(txnsToKill);
         while (!work.isEmpty()) {
             final Transaction tx = work.poll();
             log.warn("TX {} killed{}", tx.getHashAsString(),
@@ -2544,7 +2544,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addChangeEventListener(Executor executor, WalletChangeEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        changeListeners.add(new ListenerRegistration<WalletChangeEventListener>(listener, executor));
+        changeListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2561,7 +2561,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addCoinsReceivedEventListener(Executor executor, WalletCoinsReceivedEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        coinsReceivedListeners.add(new ListenerRegistration<WalletCoinsReceivedEventListener>(listener, executor));
+        coinsReceivedListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2578,7 +2578,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addCoinsSentEventListener(Executor executor, WalletCoinsSentEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        coinsSentListeners.add(new ListenerRegistration<WalletCoinsSentEventListener>(listener, executor));
+        coinsSentListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2611,7 +2611,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addReorganizeEventListener(Executor executor, WalletReorganizeEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        reorganizeListeners.add(new ListenerRegistration<WalletReorganizeEventListener>(listener, executor));
+        reorganizeListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2628,7 +2628,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addScriptChangeEventListener(Executor executor, ScriptsChangeEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        scriptChangeListeners.add(new ListenerRegistration<ScriptsChangeEventListener>(listener, executor));
+        scriptChangeListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2645,7 +2645,7 @@ public class Wallet extends BaseTaggableObject
      */
     public void addTransactionConfidenceEventListener(Executor executor, TransactionConfidenceEventListener listener) {
         // This is thread safe, so we don't need to take the lock.
-        transactionConfidenceListeners.add(new ListenerRegistration<TransactionConfidenceEventListener>(listener, executor));
+        transactionConfidenceListeners.add(new ListenerRegistration<>(listener, executor));
     }
 
     /**
@@ -2812,7 +2812,7 @@ public class Wallet extends BaseTaggableObject
     public Set<Transaction> getTransactions(boolean includeDead) {
         lock.lock();
         try {
-            Set<Transaction> all = new HashSet<Transaction>();
+            Set<Transaction> all = new HashSet<>();
             all.addAll(unspent.values());
             all.addAll(spent.values());
             all.addAll(pending.values());
@@ -2830,7 +2830,7 @@ public class Wallet extends BaseTaggableObject
     public Iterable<WalletTransaction> getWalletTransactions() {
         lock.lock();
         try {
-            Set<WalletTransaction> all = new HashSet<WalletTransaction>();
+            Set<WalletTransaction> all = new HashSet<>();
             addWalletTransactionsToSet(all, Pool.UNSPENT, unspent.values());
             addWalletTransactionsToSet(all, Pool.SPENT, spent.values());
             addWalletTransactionsToSet(all, Pool.DEAD, dead.values());
@@ -2919,7 +2919,7 @@ public class Wallet extends BaseTaggableObject
             if (numTransactions > size || numTransactions == 0) {
                 numTransactions = size;
             }
-            ArrayList<Transaction> all = new ArrayList<Transaction>(getTransactions(includeDead));
+            ArrayList<Transaction> all = new ArrayList<>(getTransactions(includeDead));
             // Order by update time.
             Collections.sort(all, Transaction.SORT_TX_BY_UPDATE_TIME);
             if (numTransactions == all.size()) {
@@ -3158,7 +3158,7 @@ public class Wallet extends BaseTaggableObject
     public List<TransactionOutput> getUnspents() {
         lock.lock();
         try {
-            return new ArrayList<TransactionOutput>(myUnspents);
+            return new ArrayList<>(myUnspents);
         } finally {
             lock.unlock();
         }
@@ -3256,7 +3256,7 @@ public class Wallet extends BaseTaggableObject
 
         final Collection<Transaction> txns;
         if (sortOrder != null) {
-            txns = new TreeSet<Transaction>(sortOrder);
+            txns = new TreeSet<>(sortOrder);
             txns.addAll(transactionMap.values());
         } else {
             txns = transactionMap.values();
@@ -3941,7 +3941,7 @@ public class Wallet extends BaseTaggableObject
                     log.warn("SendRequest transaction already has inputs but we don't know how much they are worth - they will be added to fee.");
             value = value.subtract(totalInput);
 
-            List<TransactionInput> originalInputs = new ArrayList<TransactionInput>(req.tx.getInputs());
+            List<TransactionInput> originalInputs = new ArrayList<>(req.tx.getInputs());
 
             // Check for dusty sends and the OP_RETURN limit.
             if (req.ensureMinRequiredFee && !req.emptyWallet) { // Min fee checking is handled later for emptyWallet.
@@ -4120,7 +4120,7 @@ public class Wallet extends BaseTaggableObject
         try {
             List<TransactionOutput> candidates;
             if (vUTXOProvider == null) {
-                candidates = new ArrayList<TransactionOutput>(myUnspents.size());
+                candidates = new ArrayList<>(myUnspents.size());
                 for (TransactionOutput output : myUnspents) {
                     if (excludeUnsignable && !canSignFor(output.getScriptPubKey())) continue;
                     Transaction transaction = checkNotNull(output.getParentTransaction());
@@ -4223,10 +4223,10 @@ public class Wallet extends BaseTaggableObject
      */
     protected List<UTXO> getStoredOutputsFromUTXOProvider() throws UTXOProviderException {
         UTXOProvider utxoProvider = checkNotNull(vUTXOProvider, "No UTXO provider has been set");
-        List<UTXO> candidates = new ArrayList<UTXO>();
+        List<UTXO> candidates = new ArrayList<>();
         List<ECKey> keys = getImportedKeys();
         keys.addAll(getActiveKeyChain().getLeafKeys());
-        List<Address> addresses = new ArrayList<Address>();
+        List<Address> addresses = new ArrayList<>();
         for (ECKey key : keys) {
             Address address = new Address(params, key.getPubKeyHash());
             addresses.add(address);
@@ -4421,7 +4421,7 @@ public class Wallet extends BaseTaggableObject
             for (Sha256Hash blockHash : mapBlockTx.keySet())
                 Collections.sort(mapBlockTx.get(blockHash));
 
-            List<Sha256Hash> oldBlockHashes = new ArrayList<Sha256Hash>(oldBlocks.size());
+            List<Sha256Hash> oldBlockHashes = new ArrayList<>(oldBlocks.size());
             log.info("Old part of chain (top to bottom):");
             for (StoredBlock b : oldBlocks) {
                 log.info("  {}", b.getHeader().getHashAsString());
@@ -4567,7 +4567,7 @@ public class Wallet extends BaseTaggableObject
     private void calcBloomOutPointsLocked() {
         // TODO: This could be done once and then kept up to date.
         bloomOutPoints.clear();
-        Set<Transaction> all = new HashSet<Transaction>();
+        Set<Transaction> all = new HashSet<>();
         all.addAll(unspent.values());
         all.addAll(spent.values());
         all.addAll(pending.values());
@@ -4848,7 +4848,7 @@ public class Wallet extends BaseTaggableObject
             // Of the coins we could spend, pick some that we actually will spend.
             CoinSelector selector = req.coinSelector == null ? coinSelector : req.coinSelector;
             // selector is allowed to modify candidates list.
-            CoinSelection selection = selector.select(valueNeeded, new LinkedList<TransactionOutput>(candidates));
+            CoinSelection selection = selector.select(valueNeeded, new LinkedList<>(candidates));
             // Can we afford this?
             if (selection.valueGathered.compareTo(valueNeeded) < 0) {
                 valueMissing = valueNeeded.subtract(selection.valueGathered);
@@ -5155,7 +5155,7 @@ public class Wallet extends BaseTaggableObject
             lock.unlock();
         }
         checkState(!lock.isHeldByCurrentThread());
-        ArrayList<ListenableFuture<Transaction>> futures = new ArrayList<ListenableFuture<Transaction>>(txns.size());
+        ArrayList<ListenableFuture<Transaction>> futures = new ArrayList<>(txns.size());
         TransactionBroadcaster broadcaster = vTransactionBroadcaster;
         for (Transaction tx : txns) {
             try {
diff --git a/core/src/main/java/org/bitcoinj/wallet/WalletProtobufSerializer.java b/core/src/main/java/org/bitcoinj/wallet/WalletProtobufSerializer.java
index 19ec412eb..670017c19 100644
--- a/core/src/main/java/org/bitcoinj/wallet/WalletProtobufSerializer.java
+++ b/core/src/main/java/org/bitcoinj/wallet/WalletProtobufSerializer.java
@@ -99,7 +99,7 @@ public class WalletProtobufSerializer {
     }
 
     public WalletProtobufSerializer(WalletFactory factory) {
-        txMap = new HashMap<ByteString, Transaction>();
+        txMap = new HashMap<>();
         this.factory = factory;
         this.keyChainFactory = new DefaultKeyChainFactory();
     }
@@ -577,7 +577,7 @@ public class WalletProtobufSerializer {
     }
 
     private void loadExtensions(Wallet wallet, WalletExtension[] extensionsList, Protos.Wallet walletProto) throws UnreadableWalletException {
-        final Map<String, WalletExtension> extensions = new HashMap<String, WalletExtension>();
+        final Map<String, WalletExtension> extensions = new HashMap<>();
         for (WalletExtension e : extensionsList)
             extensions.put(e.getWalletExtensionID(), e);
         // The Wallet object, if subclassed, might have added some extensions to itself already. In that case, don't
diff --git a/core/src/test/java/org/bitcoinj/core/AbstractFullPrunedBlockChainTest.java b/core/src/test/java/org/bitcoinj/core/AbstractFullPrunedBlockChainTest.java
index aa93a1884..74e7d39ac 100644
--- a/core/src/test/java/org/bitcoinj/core/AbstractFullPrunedBlockChainTest.java
+++ b/core/src/test/java/org/bitcoinj/core/AbstractFullPrunedBlockChainTest.java
@@ -193,12 +193,12 @@ public abstract class AbstractFullPrunedBlockChainTest {
         rollingBlock.solve();
         
         chain.add(rollingBlock);
-        WeakReference<StoredUndoableBlock> undoBlock = new WeakReference<StoredUndoableBlock>(store.getUndoBlock(rollingBlock.getHash()));
+        WeakReference<StoredUndoableBlock> undoBlock = new WeakReference<>(store.getUndoBlock(rollingBlock.getHash()));
 
         StoredUndoableBlock storedUndoableBlock = undoBlock.get();
         assertNotNull(storedUndoableBlock);
         assertNull(storedUndoableBlock.getTransactions());
-        WeakReference<TransactionOutputChanges> changes = new WeakReference<TransactionOutputChanges>(storedUndoableBlock.getTxOutChanges());
+        WeakReference<TransactionOutputChanges> changes = new WeakReference<>(storedUndoableBlock.getTxOutChanges());
         assertNotNull(changes.get());
         storedUndoableBlock = null;   // Blank the reference so it can be GCd.
         
diff --git a/core/src/test/java/org/bitcoinj/core/BitcoindComparisonTool.java b/core/src/test/java/org/bitcoinj/core/BitcoindComparisonTool.java
index 4faa2966e..6eb5e10c0 100644
--- a/core/src/test/java/org/bitcoinj/core/BitcoindComparisonTool.java
+++ b/core/src/test/java/org/bitcoinj/core/BitcoindComparisonTool.java
@@ -62,7 +62,7 @@ public class BitcoindComparisonTool {
 
         FullBlockTestGenerator generator = new FullBlockTestGenerator(params);
         final RuleList blockList = generator.getBlocksToTest(false, runExpensiveTests, blockFile);
-        final Map<Sha256Hash, Block> preloadedBlocks = new HashMap<Sha256Hash, Block>();
+        final Map<Sha256Hash, Block> preloadedBlocks = new HashMap<>();
         final Iterator<Block> blocks = new BlockFileLoader(params, Arrays.asList(blockFile));
 
         try {
@@ -155,13 +155,13 @@ public class BitcoindComparisonTool {
                             log.info("Got a request for a header before we had even begun processing blocks!");
                             return null;
                         }
-                        LinkedList<Block> headers = new LinkedList<Block>();
+                        LinkedList<Block> headers = new LinkedList<>();
                         Block it = blockList.hashHeaderMap.get(currentBlock.block.getHash());
                         while (it != null) {
                             headers.addFirst(it);
                             it = blockList.hashHeaderMap.get(it.getPrevBlockHash());
                         }
-                        LinkedList<Block> sendHeaders = new LinkedList<Block>();
+                        LinkedList<Block> sendHeaders = new LinkedList<>();
                         boolean found = false;
                         for (Sha256Hash hash : ((GetHeadersMessage) m).getLocator()) {
                             for (Block b : headers) {
@@ -207,7 +207,7 @@ public class BitcoindComparisonTool {
 
         connectedFuture.get();
 
-        ArrayList<Sha256Hash> locator = new ArrayList<Sha256Hash>(1);
+        ArrayList<Sha256Hash> locator = new ArrayList<>(1);
         locator.add(params.getGenesisBlock().getHash());
         Sha256Hash hashTo = Sha256Hash.wrap("0000000000000000000000000000000000000000000000000000000000000000");
                 
@@ -318,7 +318,7 @@ public class BitcoindComparisonTool {
                     log.error("ERROR: bitcoind had a non-empty mempool, but we expected an empty one on rule " + rule.ruleName);
                     rulesSinceFirstFail++;
                 } else if (mostRecentInv != null) {
-                    Set<InventoryItem> originalRuleSet = new HashSet<InventoryItem>(((MemoryPoolState)rule).mempool);
+                    Set<InventoryItem> originalRuleSet = new HashSet<>(((MemoryPoolState)rule).mempool);
                     boolean matches = mostRecentInv.items.size() == ((MemoryPoolState)rule).mempool.size();
                     for (InventoryItem item : mostRecentInv.items)
                         if (!((MemoryPoolState) rule).mempool.remove(item))
diff --git a/core/src/test/java/org/bitcoinj/core/ChainSplitTest.java b/core/src/test/java/org/bitcoinj/core/ChainSplitTest.java
index 9d406b18b..072281cab 100644
--- a/core/src/test/java/org/bitcoinj/core/ChainSplitTest.java
+++ b/core/src/test/java/org/bitcoinj/core/ChainSplitTest.java
@@ -400,7 +400,7 @@ public class ChainSplitTest {
     public void txConfidenceLevels() throws Exception {
         // Check that as the chain forks and re-orgs, the confidence data associated with each transaction is
         // maintained correctly.
-        final ArrayList<Transaction> txns = new ArrayList<Transaction>(3);
+        final ArrayList<Transaction> txns = new ArrayList<>(3);
         wallet.addCoinsReceivedEventListener(new WalletCoinsReceivedEventListener() {
             @Override
             public void onCoinsReceived(Wallet wallet, Transaction tx, Coin prevBalance, Coin newBalance) {
@@ -558,7 +558,7 @@ public class ChainSplitTest {
         // Check that a coinbase tx is marked as dead after a reorg rather than pending as normal non-double-spent
         // transactions would be. Also check that a dead coinbase on a sidechain is resurrected if the sidechain
         // becomes the best chain once more. Finally, check that dependent transactions are killed recursively.
-        final ArrayList<Transaction> txns = new ArrayList<Transaction>(3);
+        final ArrayList<Transaction> txns = new ArrayList<>(3);
         wallet.addCoinsReceivedEventListener(Threading.SAME_THREAD, new WalletCoinsReceivedEventListener() {
             @Override
             public void onCoinsReceived(Wallet wallet, Transaction tx, Coin prevBalance, Coin newBalance) {
diff --git a/core/src/test/java/org/bitcoinj/core/FullBlockTestGenerator.java b/core/src/test/java/org/bitcoinj/core/FullBlockTestGenerator.java
index 6774a6579..6d82aec43 100644
--- a/core/src/test/java/org/bitcoinj/core/FullBlockTestGenerator.java
+++ b/core/src/test/java/org/bitcoinj/core/FullBlockTestGenerator.java
@@ -147,10 +147,10 @@ public class FullBlockTestGenerator {
     private byte[] coinbaseOutKeyPubKey;
 
     // Used to double-check that we are always using the right next-height
-    private Map<Sha256Hash, Integer> blockToHeightMap = new HashMap<Sha256Hash, Integer>();
+    private Map<Sha256Hash, Integer> blockToHeightMap = new HashMap<>();
 
-    private Map<Sha256Hash, Block> hashHeaderMap = new HashMap<Sha256Hash, Block>();
-    private Map<Sha256Hash, Sha256Hash> coinbaseBlockMap = new HashMap<Sha256Hash, Sha256Hash>();
+    private Map<Sha256Hash, Block> hashHeaderMap = new HashMap<>();
+    private Map<Sha256Hash, Sha256Hash> coinbaseBlockMap = new HashMap<>();
 
     public FullBlockTestGenerator(NetworkParameters params) {
         this.params = params;
@@ -190,7 +190,7 @@ public class FullBlockTestGenerator {
         };
         RuleList ret = new RuleList(blocks, hashHeaderMap, 10);
 
-        Queue<TransactionOutPointWithValue> spendableOutputs = new LinkedList<TransactionOutPointWithValue>();
+        Queue<TransactionOutPointWithValue> spendableOutputs = new LinkedList<>();
 
         int chainHeadHeight = 1;
         Block chainHead = params.getGenesisBlock().createNextBlockWithCoinbase(Block.BLOCK_VERSION_GENESIS, coinbaseOutKeyPubKey, chainHeadHeight);
@@ -958,7 +958,7 @@ public class FullBlockTestGenerator {
         // A block with no txn
         Block b46 = new Block(params, Block.BLOCK_VERSION_GENESIS);
         {
-            b46.transactions = new ArrayList<Transaction>();
+            b46.transactions = new ArrayList<>();
             b46.setDifficultyTarget(b44.getDifficultyTarget());
             b46.setMerkleRoot(Sha256Hash.ZERO_HASH);
 
@@ -1510,7 +1510,7 @@ public class FullBlockTestGenerator {
         blocks.add(new BlockAndValidity(b82, true, false, b82.getHash(), chainHeadHeight + 28, "b82"));
         spendableOutputs.offer(b82.getCoinbaseOutput());
 
-        HashSet<InventoryItem> post82Mempool = new HashSet<InventoryItem>();
+        HashSet<InventoryItem> post82Mempool = new HashSet<>();
         post82Mempool.add(new InventoryItem(InventoryItem.Type.Transaction, b78tx.getHash()));
         post82Mempool.add(new InventoryItem(InventoryItem.Type.Transaction, b79tx.getHash()));
         blocks.add(new MemoryPoolState(post82Mempool, "post-b82 tx resurrection"));
@@ -1693,7 +1693,7 @@ public class FullBlockTestGenerator {
             int blockCountAfter1001;
             int nextHeight = heightAfter1001;
 
-            List<Sha256Hash> hashesToSpend = new LinkedList<Sha256Hash>(); // all index 0
+            List<Sha256Hash> hashesToSpend = new LinkedList<>(); // all index 0
             final int TRANSACTION_CREATION_BLOCKS = 100;
             for (blockCountAfter1001 = 0; blockCountAfter1001 < TRANSACTION_CREATION_BLOCKS; blockCountAfter1001++) {
                 NewBlock block = createNextBlock(lastBlock, nextHeight++, null, null);
diff --git a/core/src/test/java/org/bitcoinj/core/PeerGroupTest.java b/core/src/test/java/org/bitcoinj/core/PeerGroupTest.java
index 625b89a14..a6c797cf2 100644
--- a/core/src/test/java/org/bitcoinj/core/PeerGroupTest.java
+++ b/core/src/test/java/org/bitcoinj/core/PeerGroupTest.java
@@ -77,9 +77,9 @@ public class PeerGroupTest extends TestWithPeerGroup {
     @Before
     public void setUp() throws Exception {
         super.setUp();
-        peerToMessageCount = new HashMap<Peer, AtomicInteger>();
-        connectedPeers = new LinkedBlockingQueue<Peer>();
-        disconnectedPeers = new LinkedBlockingQueue<Peer>();
+        peerToMessageCount = new HashMap<>();
+        connectedPeers = new LinkedBlockingQueue<>();
+        disconnectedPeers = new LinkedBlockingQueue<>();
         preMessageReceivedListener = new PreMessageReceivedEventListener() {
             @Override
             public Message onPreMessageReceived(Peer peer, Message m) {
@@ -207,8 +207,8 @@ public class PeerGroupTest extends TestWithPeerGroup {
         
         // Check the peer accessors.
         assertEquals(2, peerGroup.numConnectedPeers());
-        Set<Peer> tmp = new HashSet<Peer>(peerGroup.getConnectedPeers());
-        Set<Peer> expectedPeers = new HashSet<Peer>();
+        Set<Peer> tmp = new HashSet<>(peerGroup.getConnectedPeers());
+        Set<Peer> expectedPeers = new HashSet<>();
         expectedPeers.add(peerOf(p1));
         expectedPeers.add(peerOf(p2));
         assertEquals(tmp, expectedPeers);
@@ -783,7 +783,7 @@ public class PeerGroupTest extends TestWithPeerGroup {
 
         // First, grab a load of keys from the wallet, and then recreate it so it forgets that those keys were issued.
         Wallet shadow = Wallet.fromSeed(wallet.getParams(), wallet.getKeyChainSeed());
-        List<ECKey> keys = new ArrayList<ECKey>(NUM_KEYS);
+        List<ECKey> keys = new ArrayList<>(NUM_KEYS);
         for (int i = 0; i < NUM_KEYS; i++) {
             keys.add(shadow.freshReceiveKey());
         }
diff --git a/core/src/test/java/org/bitcoinj/core/PeerTest.java b/core/src/test/java/org/bitcoinj/core/PeerTest.java
index dce7e991f..fd0951bbd 100644
--- a/core/src/test/java/org/bitcoinj/core/PeerTest.java
+++ b/core/src/test/java/org/bitcoinj/core/PeerTest.java
@@ -224,7 +224,7 @@ public class PeerTest extends TestWithNetworkConnections {
         inbound(writeTarget, inv);
 
         GetBlocksMessage getblocks = (GetBlocksMessage)outbound(writeTarget);
-        List<Sha256Hash> expectedLocator = new ArrayList<Sha256Hash>();
+        List<Sha256Hash> expectedLocator = new ArrayList<>();
         expectedLocator.add(b1.getHash());
         expectedLocator.add(PARAMS.getGenesisBlock().getHash());
         
@@ -395,7 +395,7 @@ public class PeerTest extends TestWithNetworkConnections {
         });
         peer.startBlockChainDownload();
 
-        List<Sha256Hash> expectedLocator = new ArrayList<Sha256Hash>();
+        List<Sha256Hash> expectedLocator = new ArrayList<>();
         expectedLocator.add(b2.getHash());
         expectedLocator.add(b1.getHash());
         expectedLocator.add(PARAMS.getGenesisBlock().getHash());
@@ -477,7 +477,7 @@ public class PeerTest extends TestWithNetworkConnections {
         peer.setDownloadParameters(Utils.currentTimeSeconds() - (600*2) + 1, false);
         peer.startBlockChainDownload();
         GetHeadersMessage getheaders = (GetHeadersMessage) outbound(writeTarget);
-        List<Sha256Hash> expectedLocator = new ArrayList<Sha256Hash>();
+        List<Sha256Hash> expectedLocator = new ArrayList<>();
         expectedLocator.add(b1.getHash());
         expectedLocator.add(PARAMS.getGenesisBlock().getHash());
         assertEquals(getheaders.getLocator(), expectedLocator);
diff --git a/core/src/test/java/org/bitcoinj/core/TransactionTest.java b/core/src/test/java/org/bitcoinj/core/TransactionTest.java
index 34e9b27f7..ea2b21734 100644
--- a/core/src/test/java/org/bitcoinj/core/TransactionTest.java
+++ b/core/src/test/java/org/bitcoinj/core/TransactionTest.java
@@ -299,7 +299,7 @@ public class TransactionTest {
         Transaction tx3 = FakeTxBuilder.createFakeTx(PARAMS);
         tx3.getConfidence().setAppearedAtChainHeight(3);
 
-        SortedSet<Transaction> set = new TreeSet<Transaction>(Transaction.SORT_TX_BY_HEIGHT);
+        SortedSet<Transaction> set = new TreeSet<>(Transaction.SORT_TX_BY_HEIGHT);
         set.add(tx2);
         set.add(tx1);
         set.add(tx3);
diff --git a/core/src/test/java/org/bitcoinj/crypto/MnemonicCodeTest.java b/core/src/test/java/org/bitcoinj/crypto/MnemonicCodeTest.java
index 0f59546bd..4757d0bf6 100644
--- a/core/src/test/java/org/bitcoinj/crypto/MnemonicCodeTest.java
+++ b/core/src/test/java/org/bitcoinj/crypto/MnemonicCodeTest.java
@@ -213,6 +213,6 @@ public class MnemonicCodeTest {
     }
 
     public static List<String> split(String words) {
-        return new ArrayList<String>(Arrays.asList(words.split("\\s+")));
+        return new ArrayList<>(Arrays.asList(words.split("\\s+")));
     }
 }
diff --git a/core/src/test/java/org/bitcoinj/net/NetworkAbstractionTests.java b/core/src/test/java/org/bitcoinj/net/NetworkAbstractionTests.java
index e0ea38096..af0fbebd2 100644
--- a/core/src/test/java/org/bitcoinj/net/NetworkAbstractionTests.java
+++ b/core/src/test/java/org/bitcoinj/net/NetworkAbstractionTests.java
@@ -106,7 +106,7 @@ public class NetworkAbstractionTests {
                     return null;
                 }
 
-                return new ProtobufConnection<TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
+                return new ProtobufConnection<>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
                         handler.write(msg);
@@ -127,7 +127,7 @@ public class NetworkAbstractionTests {
         server.startAsync();
         server.awaitRunning();
 
-        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public synchronized void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -149,7 +149,7 @@ public class NetworkAbstractionTests {
         client1ConnectionOpened.get();
         client1Disconnected.get();
 
-        clientHandler = new ProtobufConnection<TwoWayChannelMessage>(
+        clientHandler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public synchronized void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -198,7 +198,7 @@ public class NetworkAbstractionTests {
         NioServer server = new NioServer(new StreamConnectionFactory() {
             @Override
             public ProtobufConnection<TwoWayChannelMessage> getNewConnection(InetAddress inetAddress, int port) {
-                return new ProtobufConnection<TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
+                return new ProtobufConnection<>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
                         handler.write(msg);
@@ -220,7 +220,7 @@ public class NetworkAbstractionTests {
         server.startAsync();
         server.awaitRunning();
 
-        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public synchronized void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -276,7 +276,7 @@ public class NetworkAbstractionTests {
         NioServer server = new NioServer(new StreamConnectionFactory() {
             @Override
             public ProtobufConnection<TwoWayChannelMessage> getNewConnection(InetAddress inetAddress, int port) {
-                return new ProtobufConnection<TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
+                return new ProtobufConnection<>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
                         fail.set(true);
@@ -304,7 +304,7 @@ public class NetworkAbstractionTests {
         server.startAsync();
         server.awaitRunning();
 
-        openConnection(new InetSocketAddress("localhost", 4243), new ProtobufConnection<TwoWayChannelMessage>(
+        openConnection(new InetSocketAddress("localhost", 4243), new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -329,7 +329,7 @@ public class NetworkAbstractionTests {
         serverConnection1Closed.get();
         long closeDelayFinish = System.currentTimeMillis();
 
-        ProtobufConnection<TwoWayChannelMessage> client2Handler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> client2Handler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -375,7 +375,7 @@ public class NetworkAbstractionTests {
         NioServer server = new NioServer(new StreamConnectionFactory() {
             @Override
             public ProtobufConnection<TwoWayChannelMessage> getNewConnection(InetAddress inetAddress, int port) {
-                return new ProtobufConnection<TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
+                return new ProtobufConnection<>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
                         handler.write(msg);
@@ -396,7 +396,7 @@ public class NetworkAbstractionTests {
         server.startAsync();
         server.awaitRunning();
 
-        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> clientHandler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public synchronized void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -526,7 +526,7 @@ public class NetworkAbstractionTests {
         NioServer server = new NioServer(new StreamConnectionFactory() {
             @Override
             public ProtobufConnection<TwoWayChannelMessage> getNewConnection(InetAddress inetAddress, int port) {
-                return new ProtobufConnection<TwoWayChannelMessage>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
+                return new ProtobufConnection<>(new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
                         handler.write(msg);
@@ -560,7 +560,7 @@ public class NetworkAbstractionTests {
         server.startAsync();
         server.awaitRunning();
 
-        ProtobufConnection<TwoWayChannelMessage> client1Handler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> client1Handler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -582,7 +582,7 @@ public class NetworkAbstractionTests {
         client1ConnectionOpen.get();
         serverConnection1Open.get();
 
-        ProtobufConnection<TwoWayChannelMessage> client2Handler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> client2Handler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
@@ -604,7 +604,7 @@ public class NetworkAbstractionTests {
         client2ConnectionOpen.get();
         serverConnection2Open.get();
 
-        ProtobufConnection<TwoWayChannelMessage> client3Handler = new ProtobufConnection<TwoWayChannelMessage>(
+        ProtobufConnection<TwoWayChannelMessage> client3Handler = new ProtobufConnection<>(
                 new ProtobufConnection.Listener<Protos.TwoWayChannelMessage>() {
                     @Override
                     public void messageReceived(ProtobufConnection<TwoWayChannelMessage> handler, Protos.TwoWayChannelMessage msg) {
diff --git a/core/src/test/java/org/bitcoinj/protocols/channels/ChannelConnectionTest.java b/core/src/test/java/org/bitcoinj/protocols/channels/ChannelConnectionTest.java
index eb2d7f257..4edeb3d2a 100644
--- a/core/src/test/java/org/bitcoinj/protocols/channels/ChannelConnectionTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/channels/ChannelConnectionTest.java
@@ -124,7 +124,7 @@ public class ChannelConnectionTest extends TestWithWallet {
 
         // Set up a way to monitor broadcast transactions. When you expect a broadcast, you must release a permit
         // to the broadcastTxPause semaphore so state can be queried in between.
-        broadcasts = new LinkedBlockingQueue<Transaction>();
+        broadcasts = new LinkedBlockingQueue<>();
         broadcastTxPause = new Semaphore(0);
         mockBroadcaster = new TransactionBroadcaster() {
             @Override
@@ -177,7 +177,7 @@ public class ChannelConnectionTest extends TestWithWallet {
         // Test with network code and without any issues. We'll broadcast two txns: multisig contract and settle transaction.
         final SettableFuture<ListenableFuture<PaymentChannelV1ServerState>> serverCloseFuture = SettableFuture.create();
         final SettableFuture<Sha256Hash> channelOpenFuture = SettableFuture.create();
-        final BlockingQueue<ChannelTestUtils.UpdatePair> q = new LinkedBlockingQueue<ChannelTestUtils.UpdatePair>();
+        final BlockingQueue<ChannelTestUtils.UpdatePair> q = new LinkedBlockingQueue<>();
         final PaymentChannelServerListener server = new PaymentChannelServerListener(mockBroadcaster, serverWallet, 30, COIN,
                 new PaymentChannelServerListener.HandlerFactory() {
                     @Nullable
diff --git a/core/src/test/java/org/bitcoinj/protocols/channels/ChannelTestUtils.java b/core/src/test/java/org/bitcoinj/protocols/channels/ChannelTestUtils.java
index 1677242fa..29b66d585 100644
--- a/core/src/test/java/org/bitcoinj/protocols/channels/ChannelTestUtils.java
+++ b/core/src/test/java/org/bitcoinj/protocols/channels/ChannelTestUtils.java
@@ -39,7 +39,7 @@ import static org.junit.Assert.assertEquals;
  */
 public class ChannelTestUtils {
     public static class RecordingServerConnection implements PaymentChannelServer.ServerConnection {
-        public BlockingQueue<Object> q = new LinkedBlockingQueue<Object>();
+        public BlockingQueue<Object> q = new LinkedBlockingQueue<>();
 
         @Override
         public void sendToClient(Protos.TwoWayChannelMessage msg) {
@@ -85,7 +85,7 @@ public class ChannelTestUtils {
     }
 
     public static class RecordingClientConnection implements PaymentChannelClient.ClientConnection {
-        public BlockingQueue<Object> q = new LinkedBlockingQueue<Object>();
+        public BlockingQueue<Object> q = new LinkedBlockingQueue<>();
         static final int IGNORE_EXPIRE = -1;
         private final int maxExpireTime;
 
diff --git a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelClientTest.java b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelClientTest.java
index 25d04acde..3190868a0 100644
--- a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelClientTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelClientTest.java
@@ -85,7 +85,7 @@ public class PaymentChannelClientTest {
         maxValue = Coin.COIN;
         serverHash = Sha256Hash.of("serverId".getBytes());
         connection = createMock(IPaymentChannelClient.ClientConnection.class);
-        clientVersionCapture = new Capture<TwoWayChannelMessage>();
+        clientVersionCapture = new Capture<>();
     }
 
     @Test
diff --git a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelServerTest.java b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelServerTest.java
index 5fd817258..716405302 100644
--- a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelServerTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelServerTest.java
@@ -69,7 +69,7 @@ public class PaymentChannelServerTest {
     @Test
     public void shouldAcceptDefaultTimeWindow() {
         final TwoWayChannelMessage message = createClientVersionMessage();
-        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<TwoWayChannelMessage>();
+        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<>();
         connection.sendToClient(capture(initiateCapture));
         replay(connection);
 
@@ -88,7 +88,7 @@ public class PaymentChannelServerTest {
         final int minTimeWindow = 20000;
         final int timeWindow = minTimeWindow - 1;
         final TwoWayChannelMessage message = createClientVersionMessage(timeWindow);
-        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<TwoWayChannelMessage>();
+        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<>();
         connection.sendToClient(capture(initiateCapture));
 
         replay(connection);
@@ -116,7 +116,7 @@ public class PaymentChannelServerTest {
         final int maxTimeWindow = 40000;
         final int timeWindow = maxTimeWindow + 1;
         final TwoWayChannelMessage message = createClientVersionMessage(timeWindow);
-        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<TwoWayChannelMessage>();
+        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<>();
         connection.sendToClient(capture(initiateCapture));
         replay(connection);
 
@@ -162,7 +162,7 @@ public class PaymentChannelServerTest {
     @Test
     public void shouldAllowExactTimeWindow() {
         final TwoWayChannelMessage message = createClientVersionMessage();
-        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<TwoWayChannelMessage>();
+        final Capture<TwoWayChannelMessage> initiateCapture = new Capture<>();
         connection.sendToClient(capture(initiateCapture));
         replay(connection);
         final int expire = 24 * 60 * 60 - 60;  // This the default defined in paymentchannel.proto
diff --git a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelStateTest.java b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelStateTest.java
index bce67c4e3..98e9be8eb 100644
--- a/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelStateTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/channels/PaymentChannelStateTest.java
@@ -105,7 +105,7 @@ public class PaymentChannelStateTest extends TestWithWallet {
         serverKey = serverWallet.freshReceiveKey();
         chain.addWallet(serverWallet);
 
-        broadcasts = new LinkedBlockingQueue<TxFuturePair>();
+        broadcasts = new LinkedBlockingQueue<>();
         mockBroadcaster = new TransactionBroadcaster() {
             @Override
             public TransactionBroadcast broadcastTransaction(Transaction tx) {
diff --git a/core/src/test/java/org/bitcoinj/protocols/payments/PaymentProtocolTest.java b/core/src/test/java/org/bitcoinj/protocols/payments/PaymentProtocolTest.java
index f7c805fce..ab8a7c0bf 100644
--- a/core/src/test/java/org/bitcoinj/protocols/payments/PaymentProtocolTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/payments/PaymentProtocolTest.java
@@ -121,7 +121,7 @@ public class PaymentProtocolTest {
     @Test
     public void testPaymentMessage() throws Exception {
         // Create
-        List<Transaction> transactions = new LinkedList<Transaction>();
+        List<Transaction> transactions = new LinkedList<>();
         transactions.add(FakeTxBuilder.createFakeTx(NETWORK_PARAMS, AMOUNT, TO_ADDRESS));
         Coin refundAmount = Coin.SATOSHI;
         Address refundAddress = new ECKey().toAddress(NETWORK_PARAMS);
diff --git a/core/src/test/java/org/bitcoinj/protocols/payments/PaymentSessionTest.java b/core/src/test/java/org/bitcoinj/protocols/payments/PaymentSessionTest.java
index 41d5de3af..dd6da6fd4 100644
--- a/core/src/test/java/org/bitcoinj/protocols/payments/PaymentSessionTest.java
+++ b/core/src/test/java/org/bitcoinj/protocols/payments/PaymentSessionTest.java
@@ -69,7 +69,7 @@ public class PaymentSessionTest {
         // Send the payment and verify that the correct information is sent.
         // Add a dummy input to tx so it is considered valid.
         tx.addInput(new TransactionInput(PARAMS, tx, outputToMe.getScriptBytes()));
-        ArrayList<Transaction> txns = new ArrayList<Transaction>();
+        ArrayList<Transaction> txns = new ArrayList<>();
         txns.add(tx);
         Address refundAddr = new Address(PARAMS, serverKey.getPubKeyHash());
         paymentSession.sendPayment(txns, refundAddr, paymentMemo);
@@ -109,7 +109,7 @@ public class PaymentSessionTest {
         // Send the payment and verify that an exception is thrown.
         // Add a dummy input to tx so it is considered valid.
         tx.addInput(new TransactionInput(PARAMS, tx, outputToMe.getScriptBytes()));
-        ArrayList<Transaction> txns = new ArrayList<Transaction>();
+        ArrayList<Transaction> txns = new ArrayList<>();
         txns.add(tx);
         try {
             paymentSession.sendPayment(txns, null, null);
@@ -140,7 +140,7 @@ public class PaymentSessionTest {
         // Send the payment and verify that the correct information is sent.
         // Add a dummy input to tx so it is considered valid.
         tx.addInput(new TransactionInput(PARAMS, tx, outputToMe.getScriptBytes()));
-        ArrayList<Transaction> txns = new ArrayList<Transaction>();
+        ArrayList<Transaction> txns = new ArrayList<>();
         txns.add(tx);
         Address refundAddr = new Address(PARAMS, serverKey.getPubKeyHash());
         paymentSession.sendPayment(txns, refundAddr, paymentMemo);
@@ -187,7 +187,7 @@ public class PaymentSessionTest {
     }
 
     private class MockPaymentSession extends PaymentSession {
-        private ArrayList<PaymentLogItem> paymentLog = new ArrayList<PaymentLogItem>();
+        private ArrayList<PaymentLogItem> paymentLog = new ArrayList<>();
 
         public MockPaymentSession(Protos.PaymentRequest request) throws PaymentProtocolException {
             super(request);
diff --git a/core/src/test/java/org/bitcoinj/script/ScriptTest.java b/core/src/test/java/org/bitcoinj/script/ScriptTest.java
index 056a636c6..ddaadd841 100644
--- a/core/src/test/java/org/bitcoinj/script/ScriptTest.java
+++ b/core/src/test/java/org/bitcoinj/script/ScriptTest.java
@@ -90,7 +90,7 @@ public class ScriptTest {
         assertTrue(ScriptBuilder.createMultiSigOutputScript(2, keys).isSentToMultiSig());
         Script script = ScriptBuilder.createMultiSigOutputScript(3, keys);
         assertTrue(script.isSentToMultiSig());
-        List<ECKey> pubkeys = new ArrayList<ECKey>(3);
+        List<ECKey> pubkeys = new ArrayList<>(3);
         for (ECKey key : keys) pubkeys.add(ECKey.fromPublicOnly(key.getPubKeyPoint()));
         assertEquals(script.getPubKeys(), pubkeys);
         assertFalse(ScriptBuilder.createOutputScript(new ECKey()).isSentToMultiSig());
@@ -228,7 +228,7 @@ public class ScriptTest {
         tx.addInput(new TransactionInput(PARAMS, tx, new byte[] {}));
         Script script = new ScriptBuilder().smallNum(0).build();
 
-        LinkedList<byte[]> stack = new LinkedList<byte[]>();
+        LinkedList<byte[]> stack = new LinkedList<>();
         Script.executeScript(tx, 0, script, stack, Script.ALL_VERIFY_FLAGS);
         assertEquals("OP_0 push length", 0, stack.get(0).length);
     }
@@ -321,7 +321,7 @@ public class ScriptTest {
     }
     
     private Map<TransactionOutPoint, Script> parseScriptPubKeys(JsonNode inputs) throws IOException {
-        Map<TransactionOutPoint, Script> scriptPubKeys = new HashMap<TransactionOutPoint, Script>();
+        Map<TransactionOutPoint, Script> scriptPubKeys = new HashMap<>();
         for (JsonNode input : inputs) {
             String hash = input.get(0).asText();
             int index = input.get(1).asInt();
@@ -383,7 +383,7 @@ public class ScriptTest {
 
             // Bitcoin Core checks this case in CheckTransaction, but we leave it to
             // later where we will see an attempt to double-spend, so we explicitly check here
-            HashSet<TransactionOutPoint> set = new HashSet<TransactionOutPoint>();
+            HashSet<TransactionOutPoint> set = new HashSet<>();
             for (TransactionInput input : transaction.getInputs()) {
                 if (set.contains(input.getOutpoint()))
                     valid = false;
diff --git a/core/src/test/java/org/bitcoinj/store/WalletProtobufSerializerTest.java b/core/src/test/java/org/bitcoinj/store/WalletProtobufSerializerTest.java
index 304c96204..6005e7571 100644
--- a/core/src/test/java/org/bitcoinj/store/WalletProtobufSerializerTest.java
+++ b/core/src/test/java/org/bitcoinj/store/WalletProtobufSerializerTest.java
@@ -233,7 +233,7 @@ public class WalletProtobufSerializerTest {
 
         BlockChain chain = new BlockChain(PARAMS, myWallet, new MemoryBlockStore(PARAMS));
 
-        final ArrayList<Transaction> txns = new ArrayList<Transaction>(2);
+        final ArrayList<Transaction> txns = new ArrayList<>(2);
         myWallet.addCoinsReceivedEventListener(new WalletCoinsReceivedEventListener() {
             @Override
             public void onCoinsReceived(Wallet wallet, Transaction tx, Coin prevBalance, Coin newBalance) {
diff --git a/core/src/test/java/org/bitcoinj/testing/InboundMessageQueuer.java b/core/src/test/java/org/bitcoinj/testing/InboundMessageQueuer.java
index 309b2f0fa..24519e386 100644
--- a/core/src/test/java/org/bitcoinj/testing/InboundMessageQueuer.java
+++ b/core/src/test/java/org/bitcoinj/testing/InboundMessageQueuer.java
@@ -29,8 +29,8 @@ import java.util.concurrent.BlockingQueue;
  * An extension of {@link org.bitcoinj.core.PeerSocketHandler} that keeps inbound messages in a queue for later processing
  */
 public abstract class InboundMessageQueuer extends PeerSocketHandler {
-    public final BlockingQueue<Message> inboundMessages = new ArrayBlockingQueue<Message>(1000);
-    public final Map<Long, SettableFuture<Void>> mapPingFutures = new HashMap<Long, SettableFuture<Void>>();
+    public final BlockingQueue<Message> inboundMessages = new ArrayBlockingQueue<>(1000);
+    public final Map<Long, SettableFuture<Void>> mapPingFutures = new HashMap<>();
 
     public Peer peer;
     public BloomFilter lastReceivedFilter;
diff --git a/core/src/test/java/org/bitcoinj/testing/MockTransactionBroadcaster.java b/core/src/test/java/org/bitcoinj/testing/MockTransactionBroadcaster.java
index 3a2935eee..9173cf046 100644
--- a/core/src/test/java/org/bitcoinj/testing/MockTransactionBroadcaster.java
+++ b/core/src/test/java/org/bitcoinj/testing/MockTransactionBroadcaster.java
@@ -52,7 +52,7 @@ public class MockTransactionBroadcaster implements TransactionBroadcaster {
         }
     }
 
-    private final LinkedBlockingQueue<TxFuturePair> broadcasts = new LinkedBlockingQueue<TxFuturePair>();
+    private final LinkedBlockingQueue<TxFuturePair> broadcasts = new LinkedBlockingQueue<>();
 
     /** Sets this mock broadcaster on the given wallet. */
     public MockTransactionBroadcaster(Wallet wallet) {
diff --git a/core/src/test/java/org/bitcoinj/testing/TestWithNetworkConnections.java b/core/src/test/java/org/bitcoinj/testing/TestWithNetworkConnections.java
index b44b2547b..6d9bcebb5 100644
--- a/core/src/test/java/org/bitcoinj/testing/TestWithNetworkConnections.java
+++ b/core/src/test/java/org/bitcoinj/testing/TestWithNetworkConnections.java
@@ -59,7 +59,7 @@ public class TestWithNetworkConnections {
 
     private NioServer[] peerServers = new NioServer[PEER_SERVERS];
     private final ClientConnectionManager channels;
-    protected final BlockingQueue<InboundMessageQueuer> newPeerWriteTargetQueue = new LinkedBlockingQueue<InboundMessageQueuer>();
+    protected final BlockingQueue<InboundMessageQueuer> newPeerWriteTargetQueue = new LinkedBlockingQueue<>();
 
     public enum ClientType {
         NIO_CLIENT_MANAGER,
diff --git a/core/src/test/java/org/bitcoinj/utils/BtcFormatTest.java b/core/src/test/java/org/bitcoinj/utils/BtcFormatTest.java
index 598498f5c..597250635 100644
--- a/core/src/test/java/org/bitcoinj/utils/BtcFormatTest.java
+++ b/core/src/test/java/org/bitcoinj/utils/BtcFormatTest.java
@@ -44,7 +44,7 @@ public class BtcFormatTest {
 
     @Parameters
     public static Set<Locale[]> data() {
-        Set<Locale[]> localeSet = new HashSet<Locale[]>();
+        Set<Locale[]> localeSet = new HashSet<>();
         for (Locale locale : Locale.getAvailableLocales()) {
             localeSet.add(new Locale[]{locale});
         }
diff --git a/core/src/test/java/org/bitcoinj/utils/ExponentialBackoffTest.java b/core/src/test/java/org/bitcoinj/utils/ExponentialBackoffTest.java
index 5add9cad3..10c78041d 100644
--- a/core/src/test/java/org/bitcoinj/utils/ExponentialBackoffTest.java
+++ b/core/src/test/java/org/bitcoinj/utils/ExponentialBackoffTest.java
@@ -60,7 +60,7 @@ public class ExponentialBackoffTest {
 
     @Test
     public void testInQueue() {
-        PriorityQueue<ExponentialBackoff> queue = new PriorityQueue<ExponentialBackoff>();
+        PriorityQueue<ExponentialBackoff> queue = new PriorityQueue<>();
         ExponentialBackoff backoff1 = new ExponentialBackoff(params);
         backoff.trackFailure();
         backoff.trackFailure();
diff --git a/core/src/test/java/org/bitcoinj/wallet/BasicKeyChainTest.java b/core/src/test/java/org/bitcoinj/wallet/BasicKeyChainTest.java
index a3de7ff8b..15a2cc8d5 100644
--- a/core/src/test/java/org/bitcoinj/wallet/BasicKeyChainTest.java
+++ b/core/src/test/java/org/bitcoinj/wallet/BasicKeyChainTest.java
@@ -50,7 +50,7 @@ public class BasicKeyChainTest {
     @Before
     public void setup() {
         chain = new BasicKeyChain();
-        onKeysAdded = new AtomicReference<List<ECKey>>();
+        onKeysAdded = new AtomicReference<>();
         onKeysAddedRan = new AtomicBoolean();
         chain.addEventListener(new AbstractKeyChainEventListener() {
             @Override
diff --git a/core/src/test/java/org/bitcoinj/wallet/DefaultCoinSelectorTest.java b/core/src/test/java/org/bitcoinj/wallet/DefaultCoinSelectorTest.java
index 20d651966..afaa05987 100644
--- a/core/src/test/java/org/bitcoinj/wallet/DefaultCoinSelectorTest.java
+++ b/core/src/test/java/org/bitcoinj/wallet/DefaultCoinSelectorTest.java
@@ -78,7 +78,7 @@ public class DefaultCoinSelectorTest extends TestWithWallet {
         assertEquals(COIN, selection.valueGathered);
 
         // Check we ordered them correctly (by depth).
-        ArrayList<TransactionOutput> candidates = new ArrayList<TransactionOutput>();
+        ArrayList<TransactionOutput> candidates = new ArrayList<>();
         candidates.add(t2.getOutput(0));
         candidates.add(t1.getOutput(0));
         DefaultCoinSelector.sortOutputs(candidates);
@@ -98,7 +98,7 @@ public class DefaultCoinSelectorTest extends TestWithWallet {
         Transaction t3 = checkNotNull(sendMoneyToWallet(AbstractBlockChain.NewBlockType.BEST_CHAIN, CENT));
 
         // Should be ordered t2, t1, t3.
-        ArrayList<TransactionOutput> candidates = new ArrayList<TransactionOutput>();
+        ArrayList<TransactionOutput> candidates = new ArrayList<>();
         candidates.add(t3.getOutput(0));
         candidates.add(t2.getOutput(0));
         candidates.add(t1.getOutput(0));
diff --git a/core/src/test/java/org/bitcoinj/wallet/KeyChainGroupTest.java b/core/src/test/java/org/bitcoinj/wallet/KeyChainGroupTest.java
index f1b06dab3..8fd3dab3a 100644
--- a/core/src/test/java/org/bitcoinj/wallet/KeyChainGroupTest.java
+++ b/core/src/test/java/org/bitcoinj/wallet/KeyChainGroupTest.java
@@ -389,7 +389,7 @@ public class KeyChainGroupTest {
     public void events() throws Exception {
         // Check that events are registered with the right chains and that if a chain is added, it gets the event
         // listeners attached properly even post-hoc.
-        final AtomicReference<ECKey> ran = new AtomicReference<ECKey>(null);
+        final AtomicReference<ECKey> ran = new AtomicReference<>(null);
         final KeyChainEventListener listener = new KeyChainEventListener() {
             @Override
             public void onKeysAdded(List<ECKey> keys) {
diff --git a/core/src/test/java/org/bitcoinj/wallet/WalletTest.java b/core/src/test/java/org/bitcoinj/wallet/WalletTest.java
index e86dbafe0..fe7108935 100644
--- a/core/src/test/java/org/bitcoinj/wallet/WalletTest.java
+++ b/core/src/test/java/org/bitcoinj/wallet/WalletTest.java
@@ -563,7 +563,7 @@ public class WalletTest extends TestWithWallet {
         // Test that we correctly process transactions arriving from the chain, with callbacks for inbound and outbound.
         final Coin[] bigints = new Coin[4];
         final Transaction[] txn = new Transaction[2];
-        final LinkedList<Transaction> confTxns = new LinkedList<Transaction>();
+        final LinkedList<Transaction> confTxns = new LinkedList<>();
         wallet.addCoinsReceivedEventListener(new WalletCoinsReceivedEventListener() {
             @Override
             public void onCoinsReceived(Wallet wallet, Transaction tx, Coin prevBalance, Coin newBalance) {
@@ -813,7 +813,7 @@ public class WalletTest extends TestWithWallet {
         Transaction send3 = checkNotNull(wallet.createSend(OTHER_ADDRESS, value));
         wallet.commitTx(send3);
         assertEquals(ZERO, wallet.getBalance());
-        final LinkedList<TransactionConfidence> dead = new LinkedList<TransactionConfidence>();
+        final LinkedList<TransactionConfidence> dead = new LinkedList<>();
         final TransactionConfidence.Listener listener = new TransactionConfidence.Listener() {
             @Override
             public void onConfidenceChanged(TransactionConfidence confidence, ChangeReason reason) {
@@ -1218,7 +1218,7 @@ public class WalletTest extends TestWithWallet {
             Transaction send1c = checkNotNull(wallet.createSend(OTHER_ADDRESS, valueOf(0, 25)));
             wallet.commitTx(send1c);
             wallet.commitTx(send2);
-            Set<Transaction> txns = new HashSet<Transaction>();
+            Set<Transaction> txns = new HashSet<>();
             txns.add(send1);
             wallet.addTransactionsDependingOn(txns, wallet.getTransactions(true));
             assertEquals(3, txns.size());
@@ -1267,7 +1267,7 @@ public class WalletTest extends TestWithWallet {
             wallet.completeTx(req2c);
             Transaction send2c = req2c.tx;
 
-            Set<Transaction> unsortedTxns = new HashSet<Transaction>();
+            Set<Transaction> unsortedTxns = new HashSet<>();
             unsortedTxns.add(send1a);
             unsortedTxns.add(send1b);
             unsortedTxns.add(send1c);
@@ -1710,7 +1710,7 @@ public class WalletTest extends TestWithWallet {
 
     @Test
     public void removeWatchedAddresses() {
-        List<Address> addressesForRemoval = new ArrayList<Address>();
+        List<Address> addressesForRemoval = new ArrayList<>();
         for (int i = 0; i < 10; i++) {
             Address watchedAddress = new ECKey().toAddress(PARAMS);
             addressesForRemoval.add(watchedAddress);
@@ -1735,7 +1735,7 @@ public class WalletTest extends TestWithWallet {
 
     @Test
     public void removeScriptsBloomFilter() throws Exception {
-        List<Address> addressesForRemoval = new ArrayList<Address>();
+        List<Address> addressesForRemoval = new ArrayList<>();
         for (int i = 0; i < 10; i++) {
             Address watchedAddress = new ECKey().toAddress(PARAMS);
             addressesForRemoval.add(watchedAddress);
@@ -3069,7 +3069,7 @@ public class WalletTest extends TestWithWallet {
         goodKey.setCreationTimeSeconds(Utils.currentTimeSeconds());
 
         // Do an upgrade based on the bad key.
-        final AtomicReference<List<DeterministicKeyChain>> fChains = new AtomicReference<List<DeterministicKeyChain>>();
+        final AtomicReference<List<DeterministicKeyChain>> fChains = new AtomicReference<>();
         KeyChainGroup kcg = new KeyChainGroup(PARAMS) {
 
             {