Add StreamManagemtCounterError

to allow graceful connectionClosedOnError() disconnects, since we
received a bunch of reports where the counter seems wrong, which is
causing a NPE in a thread pool executor, causing the VM or Android App
to terminate.

Now we throw the StreamManagementCounterError instead.

smack-tcp/src/main/java/org/jivesoftware/smack/sm/StreamManagementException.java

@@ -16,7 +16,11 @@
  */
 package org.jivesoftware.smack.sm;
 
+import java.util.Collections;
+import java.util.List;
+
 import org.jivesoftware.smack.SmackException;
+import org.jivesoftware.smack.packet.Stanza;
 
 public abstract class StreamManagementException extends SmackException {
 
@@ -52,5 +56,59 @@ public abstract class StreamManagementException extends SmackException {
             super("Stream IDs do not match. Expected '" + expected + "', but got '" + got + "'");
         }
     }
+
+    public static class StreamManagementCounterError extends StreamManagementException {
+
+        /**
+         *
+         */
+        private static final long serialVersionUID = 1L;
+
+        private final long handledCount;
+        private final long previousServerHandledCount;
+        private final long ackedStanzaCount;
+        private final int outstandingStanzasCount;
+        private final List<Stanza> ackedStanzas;
+
+        public StreamManagementCounterError(long handledCount, long previousServerHandlerCount,
+                        long ackedStanzaCount,
+                        List<Stanza> ackedStanzas) {
+            super(
+                            "There was an error regarding the Stream Mangement counters. Server reported "
+                                            + handledCount
+                                            + " handled stanzas, which means that the "
+                                            + ackedStanzaCount
+                                            + " recently send stanzas by client are now acked by the server. But Smack had only "
+                                            + ackedStanzas.size()
+                                            + " to acknowledge. The stanza id of the last acked outstanding stanza is "
+                                            + (ackedStanzas.isEmpty() ? "<no acked stanzas>"
+                                                            : ackedStanzas.get(ackedStanzas.size() - 1).getStanzaId()));
+            this.handledCount = handledCount;
+            this.previousServerHandledCount = previousServerHandlerCount;
+            this.ackedStanzaCount = ackedStanzaCount;
+            this.outstandingStanzasCount = ackedStanzas.size();
+            this.ackedStanzas = Collections.unmodifiableList(ackedStanzas);
+        }
+
+        public long getHandledCount() {
+            return handledCount;
+        }
+
+        public long getPreviousServerHandledCount() {
+            return previousServerHandledCount;
+        }
+
+        public long getAckedStanzaCount() {
+            return ackedStanzaCount;
+        }
+
+        public int getOutstandingStanzasCount() {
+            return outstandingStanzasCount;
+        }
+
+        public List<Stanza> getAckedStanzas() {
+            return ackedStanzas;
+        }
+    }
 }
 

smack-tcp/src/main/java/org/jivesoftware/smack/tcp/XMPPTCPConnection.java

@@ -54,6 +54,7 @@ import org.jivesoftware.smack.sasl.packet.SaslStreamElements.Success;
 import org.jivesoftware.smack.sm.SMUtils;
 import org.jivesoftware.smack.sm.StreamManagementException;
 import org.jivesoftware.smack.sm.StreamManagementException.StreamIdDoesNotMatchException;
+import org.jivesoftware.smack.sm.StreamManagementException.StreamManagementCounterError;
 import org.jivesoftware.smack.sm.StreamManagementException.StreamManagementNotEnabledException;
 import org.jivesoftware.smack.sm.packet.StreamManagement;
 import org.jivesoftware.smack.sm.packet.StreamManagement.AckAnswer;
@@ -1642,7 +1643,7 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
         return Math.min(clientResumptionTime, serverResumptionTime);
     }
 
-    private void processHandledCount(long handledCount) throws NotConnectedException {
+    private void processHandledCount(long handledCount) throws NotConnectedException, StreamManagementCounterError {
         long ackedStanzasCount = SMUtils.calculateDelta(handledCount, serverHandledStanzasCount);
         final List<Stanza> ackedStanzas = new ArrayList<Stanza>(
                         handledCount <= Integer.MAX_VALUE ? (int) handledCount
@@ -1651,7 +1652,10 @@ public class XMPPTCPConnection extends AbstractXMPPConnection {
             Stanza ackedStanza = unacknowledgedStanzas.poll();
             // If the server ack'ed a stanza, then it must be in the
             // unacknowledged stanza queue. There can be no exception.
-            assert(ackedStanza != null);
+            if (ackedStanza == null) {
+                throw new StreamManagementCounterError(handledCount, serverHandledStanzasCount,
+                                ackedStanzasCount, ackedStanzas);
+            }
             ackedStanzas.add(ackedStanza);
         }