Connection handling fixes

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

@@ -314,6 +314,22 @@ public boolean equals(Object o) {
 
     }
 
+    public boolean equalsIgnoringMetadata(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        PeerAddress that = (PeerAddress) o;
+
+        if (port != that.port) return false;
+        // Don't compare the time field
+        // if (time != that.time) return false;
+        if (addr != null ? !addr.equals(that.addr) : that.addr != null) return false;
+        if (hostname != null ? !hostname.equals(that.hostname) : that.hostname != null) return false;
+        // Don't compare the services field
+        // return !(services != null ? !services.equals(that.services) : that.services != null);
+        return true;
+    }
+
     @Override
     public int hashCode() {
         int result = addr != null ? addr.hashCode() : 0;

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

@@ -621,16 +621,15 @@ public void go() {
                     long delay = retryTime - now;
                     log.info("Waiting {} msec before next connect attempt {}", delay, addrToTry == null ? "" : "to " + addrToTry);
 
-                    if (!isAlreadyAdded(addrToTry))
-                        inactives.add(addrToTry);
+                    inactives.add(addrToTry);
                     executor.schedule(this, delay, TimeUnit.MILLISECONDS);
                     return;
                 }
 
                 // BitcoinJ gets too many connections after a connection loss and reconnect as it adds up a lot of
                 // potential candidates and then try to connect to all of those when getting connection again.
                 // A check for maxConnections is required to not exceed connections.
-                if(pendingPeers.size() + peers.size() < maxConnections)
+                if (countConnectedAndPendingPeers() < getMaxConnections())
                     connectTo(addrToTry, false, vConnectTimeoutMillis);
             } finally {
                 lock.unlock();
@@ -641,17 +640,6 @@ public void go() {
         }
     };
 
-    private boolean isAlreadyAdded(PeerAddress peerAddress) {
-        boolean isAlreadyAdded = false;
-        for (PeerAddress a : inactives) {
-            if (a.getHostname() != null && a.getHostname().equals(peerAddress.getHostname())) {
-                isAlreadyAdded = true;
-                break;
-            }
-        }
-        return isAlreadyAdded;
-    }
-
     private void triggerConnections() {
         // Run on a background thread due to the need to potentially retry and back off in the background.
         if (!executor.isShutdown())
@@ -1048,13 +1036,18 @@ private boolean addInactive(PeerAddress peerAddress) {
         lock.lock();
         try {
             // Deduplicate
-            if (backoffMap.containsKey(peerAddress)) {
+            boolean backoffMapContainsPeerAddress = false;
+            for (PeerAddress a : backoffMap.keySet()) {
+                if (a.equalsIgnoringMetadata(peerAddress)) {
+                    backoffMapContainsPeerAddress = true;
+                    break;
+                }
+            }
+            if (backoffMapContainsPeerAddress) {
                 return false;
             }
             backoffMap.put(peerAddress, new ExponentialBackoff(peerBackoffParams));
-
-            if (!isAlreadyAdded(peerAddress))
-                inactives.offer(peerAddress);
+            inactives.offer(peerAddress);
 
             return true;
         } finally {
@@ -1249,6 +1242,7 @@ public ListenableFuture stopAsync() {
             public void run() {
                 try {
                     log.info("Stopping ...");
+                    setDownloadPeer(null);
                     // Blocking close of all sockets.
                     channels.stopAsync();
                     channels.awaitTerminated();
@@ -1848,12 +1842,6 @@ protected void handlePeerDeath(final Peer peer, @Nullable Throwable exception) {
                 if (newDownloadPeer != null) {
                     setDownloadPeer(newDownloadPeer);
 
-                    // When using BlockingClient we get errors at shutdown caused by
-                    // startBlockChainDownloadFromPeer()
-                    // We add another check to terminate here if we have been shut down already
-                    if (!isRunning())
-                        return;
-
                     if (downloadListener != null) {
                         startBlockChainDownloadFromPeer(newDownloadPeer);
                     }
@@ -1872,7 +1860,16 @@ protected void handlePeerDeath(final Peer peer, @Nullable Throwable exception) {
             } else {
                 backoffMap.get(address).trackFailure();
                 // Put back on inactive list
-                inactives.offer(address);
+                boolean inactiveContainsAddress = false;
+                for (PeerAddress a : inactives) {
+                    if (a.equalsIgnoringMetadata(address)) {
+                        inactiveContainsAddress = true;
+                        break;
+                    }
+                }
+                if (!inactiveContainsAddress) {
+                    inactives.offer(address);
+                }
             }
 
             if (numPeers < getMaxConnections()) {

core/src/main/java/org/bitcoinj/net/BlockingClient.java

@@ -149,10 +149,11 @@ public synchronized void writeBytes(byte[] message) throws IOException {
                 OutputStream stream = socket.getOutputStream();
                 stream.write(message);
                 stream.flush();
+            } else {
+                log.warn("Attempted to write to a closed socket.");
             }
         } catch (IOException e) {
-            if(!(e instanceof SocketException && e.toString().equals("Socket is closed")))
-                log.error("Error writing message to connection, closing connection", e);
+            log.error("Error writing message to connection, closing connection", e);
             closeConnection();
             throw e;
         }