Refactor the code that sets filters a bit, and send a mempool query after wallet contents change in case of a key import.

core/src/main/java/com/google/bitcoin/core/Peer.java

@@ -1241,4 +1241,35 @@ public class Peer {
             return null;
         }
     }
+
+    /**
+     * <p>Sets a Bloom filter on this connection. This will cause the given {@link BloomFilter} object to be sent to the
+     * remote peer and if either a memory pool has been set using {@link Peer#setMemoryPool(MemoryPool)} or the
+     * downloadData property is true, a {@link MemoryPoolMessage} is sent as well to trigger downloading of any
+     * pending transactions that may be relevant.</p>
+     *
+     * <p>The Peer does not keep a reference to the BloomFilter. Also, it will not automatically request filters
+     * from any wallets added using {@link Peer#addWallet(Wallet)}. This is to allow callers to avoid redundantly
+     * recalculating the same filter repeatedly when using multiple peers together.</p>
+     *
+     * <p>Therefore, you should not use this method if your app uses a {@link PeerGroup}. It is called for you.</p>
+     *
+     * <p>If the remote peer doesn't support Bloom filtering, then this call is ignored.</p>
+     */
+    public void setBloomFilter(BloomFilter filter) throws IOException {
+        if (!getPeerVersionMessage().isBloomFilteringSupported())
+            return;
+        boolean shouldQueryMemPool;
+        synchronized (this) {
+            shouldQueryMemPool = memoryPool != null || downloadData.get();
+        }
+        log.info("{}: Sending Bloom filter{}", this, shouldQueryMemPool ? " and querying mempool" : "");
+        ChannelFuture future = sendMessage(filter);
+        if (shouldQueryMemPool)
+            future.addListener(new ChannelFutureListener() {
+                public void operationComplete(ChannelFuture future) throws Exception {
+                    sendMessage(new MemoryPoolMessage());
+                }
+            });
+    }
 }

core/src/main/java/com/google/bitcoin/core/PeerGroup.java

@@ -580,16 +580,12 @@ public class PeerGroup extends AbstractIdleService {
             for (Wallet w : wallets)
                 filter.merge(w.getBloomFilter(lastBloomFilterElementCount, bloomFilterFPRate, bloomFilterTweak));
             bloomFilter = filter;
-            for (Peer peer : peers) {
+            for (Peer peer : peers)
-                if (peer.getPeerVersionMessage().isBloomFilteringSupported()) {
+                try {
-                    try {
+                    peer.setBloomFilter(filter);
-                        log.info("{}: Sending peer an updated Bloom Filter.", peer);
+                } catch (IOException e) {
-                        peer.sendMessage(filter);
+                    throw new RuntimeException(e);
-                    } catch (IOException e) {
-                        throw new RuntimeException(e);
-                    }
                 }
-            }
         }
         // Do this last so that bloomFilter is already set when it gets called.
         setFastCatchupTimeSecs(earliestKeyTime);
@@ -719,11 +715,7 @@ public class PeerGroup extends AbstractIdleService {
         // aren't relevant to our wallet. We may still receive some false positives, which is
         // OK because it helps improve wallet privacy. Old nodes will just ignore the message.
         try {
-            if (bloomFilter != null && peer.getPeerVersionMessage().isBloomFilteringSupported()) {
+            if (bloomFilter != null) peer.setBloomFilter(bloomFilter);
-                log.info("{}: Sending Bloom filter and querying memory pool", peer);
-                peer.sendMessage(bloomFilter);
-                peer.sendMessage(new MemoryPoolMessage());
-            }
         } catch (IOException e) { } // That was quick...already disconnected
         // Link the peer to the memory pool so broadcast transactions have their confidence levels updated.
         peer.setMemoryPool(memoryPool);

core/src/test/java/com/google/bitcoin/core/PeerGroupTest.java

@@ -311,12 +311,13 @@ public class PeerGroupTest extends TestWithPeerGroup {
         peerGroup.addWallet(wallet);
         // Transaction announced to the first peer.
         InventoryMessage inv1 = (InventoryMessage) outbound(p1);
+        assertTrue(outbound(p1) instanceof BloomFilter);   // Filter is recalculated.
+        assertTrue(outbound(p1) instanceof MemoryPoolMessage);
         assertEquals(t3.getHash(), inv1.getItems().get(0).hash);
         // Peer asks for the transaction, and get it.
         GetDataMessage getdata = new GetDataMessage(params);
         getdata.addItem(inv1.getItems().get(0));
         inbound(p1, getdata);
-        assertTrue(outbound(p1) instanceof BloomFilter);   // Filter is recalculated.
         Transaction t4 = (Transaction) outbound(p1);
         assertEquals(t3, t4);