VersionMessage: inline helpers isWitnessSupported(), hasBlockChain() and hasLimitedBlockChain()

Our API is now fluent enough that we don't need them any more.

core/src/main/java/org/bitcoinj/core/Peer.java

@@ -522,21 +522,22 @@ public class Peer extends PeerSocketHandler {
         // mode nodes because we can't download the data from them we need to find/verify transactions. Some bogus
         // implementations claim to have a block chain in their services field but then report a height of zero, filter
         // them out here.
-        if (!peerVersionMessage.hasLimitedBlockChain() ||
+        Services services = peerVersionMessage.services();
+        if (!(services.has(Services.NODE_NETWORK) || services.has(Services.NODE_NETWORK_LIMITED)) ||
                 (!params.allowEmptyPeerChain() && peerVersionMessage.bestHeight == 0)) {
             // Shut down the channel gracefully.
             log.info("{}: Peer does not have at least a recent part of the block chain.", this);
             close();
             return;
         }
-        if (!peerVersionMessage.localServices.has(requiredServices)) {
+        if (!services.has(requiredServices)) {
             log.info("{}: Peer doesn't support these required services: {}", this,
                     Services.of(requiredServices & ~peerVersionMessage.localServices.bits()).toString());
             // Shut down the channel gracefully.
             close();
             return;
         }
-        if (peerVersionMessage.localServices.has(Services.NODE_BITCOIN_CASH)) {
+        if (services.has(Services.NODE_BITCOIN_CASH)) {
             log.info("{}: Peer follows an incompatible block chain.", this);
             // Shut down the channel gracefully.
             close();
@@ -911,7 +912,7 @@ public class Peer extends PeerSocketHandler {
     private GetDataMessage buildMultiTransactionDataMessage(Set<Sha256Hash> txIds) {
         GetDataMessage getdata = new GetDataMessage();
         txIds.forEach(txId ->
-            getdata.addTransaction(txId, vPeerVersionMessage.isWitnessSupported()));
+                getdata.addTransaction(txId, vPeerVersionMessage.services().has(Services.NODE_WITNESS)));
         return getdata;
     }
 
@@ -1183,7 +1184,7 @@ public class Peer extends PeerSocketHandler {
             } else {
                 if (log.isDebugEnabled())
                     log.debug("{}: getdata on tx {}", getAddress(), item.hash);
-                getdata.addTransaction(item.hash, vPeerVersionMessage.isWitnessSupported());
+                getdata.addTransaction(item.hash, vPeerVersionMessage.services().has(Services.NODE_WITNESS));
                 if (pendingTxDownloads.size() > PENDING_TX_DOWNLOADS_LIMIT) {
                     log.info("{}: Too many pending transactions, disconnecting", this);
                     close();
@@ -1228,7 +1229,7 @@ public class Peer extends PeerSocketHandler {
                                 getdata.addFilteredBlock(item.hash);
                                 pingAfterGetData = true;
                             } else {
-                                getdata.addBlock(item.hash, vPeerVersionMessage.isWitnessSupported());
+                                getdata.addBlock(item.hash, vPeerVersionMessage.services().has(Services.NODE_WITNESS));
                             }
                             pendingBlockDownloads.add(item.hash);
                         }
@@ -1284,7 +1285,7 @@ public class Peer extends PeerSocketHandler {
         // TODO: Unit test this method.
         log.info("Request to fetch peer mempool tx  {}", hash);
         GetDataMessage getdata = new GetDataMessage();
-        getdata.addTransaction(hash, vPeerVersionMessage.isWitnessSupported());
+        getdata.addTransaction(hash, vPeerVersionMessage.services().has(Services.NODE_WITNESS));
         return ListenableCompletableFuture.of(sendSingleGetData(getdata));
     }
 

core/src/main/java/org/bitcoinj/core/PeerGroup.java

@@ -2377,9 +2377,9 @@ public class PeerGroup implements TransactionBroadcaster {
             final VersionMessage versionMessage = peer.getPeerVersionMessage();
             if (versionMessage.clientVersion < MINIMUM_VERSION)
                 continue;
-            if (!versionMessage.hasBlockChain())
+            if (!versionMessage.services().has(Services.NODE_NETWORK))
                 continue;
-            if (!versionMessage.isWitnessSupported())
+            if (!versionMessage.services().has(Services.NODE_WITNESS))
                 continue;
             final long peerHeight = peer.getBestHeight();
             if (peerHeight < mostCommonChainHeight || peerHeight > mostCommonChainHeight + 1)

core/src/main/java/org/bitcoinj/core/VersionMessage.java

@@ -113,6 +113,15 @@ public class VersionMessage extends Message {
         relayTxesBeforeFilter = true;
     }
 
+    /**
+     * Get the service bitfield that represents the node services being provided.
+     *
+     * @return service bitfield
+     */
+    public Services services() {
+        return localServices;
+    }
+
     @Override
     protected void parse(ByteBuffer payload) throws BufferUnderflowException, ProtocolException {
         clientVersion = (int) ByteUtils.readUint32(payload);
@@ -260,22 +269,4 @@ public class VersionMessage extends Message {
             return true;
         return false;
     }
-
-    /** Returns true if a peer can be asked for blocks and transactions including witness data. */
-    public boolean isWitnessSupported() {
-        return localServices.has(Services.NODE_WITNESS);
-    }
-
-    /**
-     * Returns true if the version message indicates the sender has a full copy of the block chain, or false if it's
-     * running in client mode (only has the headers).
-     */
-    public boolean hasBlockChain() {
-        return localServices.has(Services.NODE_NETWORK);
-    }
-
-    /** Returns true if the peer has at least the last two days worth of blockchain (BIP159). */
-    public boolean hasLimitedBlockChain() {
-        return hasBlockChain() || localServices.has(Services.NODE_NETWORK_LIMITED);
-    }
 }

core/src/test/java/org/bitcoinj/core/BitcoindComparisonTool.java

@@ -94,7 +94,7 @@ public class BitcoindComparisonTool {
         ver.localServices = Services.of(Services.NODE_NETWORK);
         final Peer bitcoind = new Peer(PARAMS, ver, PeerAddress.localhost(PARAMS),
                 new BlockChain(PARAMS, new MemoryBlockStore(PARAMS.getGenesisBlock())));
-        checkState(bitcoind.getVersionMessage().hasBlockChain());
+        checkState(bitcoind.getVersionMessage().services().has(Services.NODE_NETWORK));
 
         final BlockWrapper currentBlock = new BlockWrapper();
 

integration-test/src/test/java/org/bitcoinj/testing/TestWithNetworkConnections.java

@@ -27,6 +27,7 @@ import org.bitcoinj.core.NetworkParameters;
 import org.bitcoinj.core.Peer;
 import org.bitcoinj.core.Ping;
 import org.bitcoinj.core.Pong;
+import org.bitcoinj.core.Services;
 import org.bitcoinj.core.VersionAck;
 import org.bitcoinj.core.VersionMessage;
 import org.bitcoinj.core.listeners.PreMessageReceivedEventListener;
@@ -168,7 +169,7 @@ public class TestWithNetworkConnections {
     }
 
     protected InboundMessageQueuer connect(Peer peer, VersionMessage versionMessage) throws Exception {
-        checkArgument(versionMessage.hasBlockChain());
+        checkArgument(versionMessage.services().has(Services.NODE_NETWORK));
         final AtomicBoolean doneConnecting = new AtomicBoolean(false);
         final Thread thisThread = Thread.currentThread();
         peer.addDisconnectedEventListener((p, peerCount) -> {

integration-test/src/test/java/org/bitcoinj/testing/TestWithPeerGroup.java

@@ -146,7 +146,7 @@ public class TestWithPeerGroup extends TestWithNetworkConnections {
     }
 
     protected InboundMessageQueuer connectPeer(int id, VersionMessage versionMessage) throws Exception {
-        checkArgument(versionMessage.hasBlockChain());
+        checkArgument(versionMessage.services().has(Services.NODE_NETWORK));
         InboundMessageQueuer writeTarget = connectPeerWithoutVersionExchange(id);
         // Complete handshake with the peer - send/receive version(ack)s, receive bloom filter
         writeTarget.sendMessage(versionMessage);
@@ -163,7 +163,7 @@ public class TestWithPeerGroup extends TestWithNetworkConnections {
     // handle peer discovered by PeerGroup
     protected InboundMessageQueuer handleConnectToPeer(int id, VersionMessage versionMessage) throws Exception {
         InboundMessageQueuer writeTarget = newPeerWriteTargetQueue.take();
-        checkArgument(versionMessage.hasBlockChain());
+        checkArgument(versionMessage.services().has(Services.NODE_NETWORK));
         // Complete handshake with the peer - send/receive version(ack)s, receive bloom filter
         writeTarget.sendMessage(versionMessage);
         writeTarget.sendMessage(new VersionAck());