[ibb] Ensure InBandBytestreamManager is a singleton

InBandBytestreamManager followed an unusual pattern: Within the
connectionTermianted() callback, it would remove itself from the
'managers' map. This allowed for multiple instances of an
InBandBytestreamManager to exist for the same connection, causing all
kinds of issues.

This fixes the issue by changing InBandBytestreamManager to use the
Smack-idiomatic pattern used by managers.

We also do no longer reset the listeners if the connection is
termianted, as listeners (and handlers) typically persist until they
are explicitly removed by the user.

As positive side-effect, the number of indeterministic unit-tests,
caused by using Thread.sleep(), is reduced. The executor service in
InitiationListener was also removed, because the IQ handler is already
called asynchronously to the connections main loop.

Thanks to Anno van Vliet for reporting this.

smack-extensions/src/main/java/org/jivesoftware/smackx/bytestreams/ibb/InBandBytestreamManager.java

@@ -110,22 +110,6 @@ public final class InBandBytestreamManager extends Manager implements Bytestream
             public void connectionCreated(final XMPPConnection connection) {
                 // create the manager for this connection
                 InBandBytestreamManager.getByteStreamManager(connection);
-
-                // register shutdown listener
-                connection.addConnectionListener(new AbstractConnectionClosedListener() {
-
-                    @Override
-                    public void connectionTerminated() {
-                        InBandBytestreamManager.getByteStreamManager(connection).disableService();
-                    }
-
-                    @Override
-                    public void connected(XMPPConnection connection) {
-                        InBandBytestreamManager.getByteStreamManager(connection);
-                    }
-
-                });
-
             }
         });
     }
@@ -206,6 +190,15 @@ public final class InBandBytestreamManager extends Manager implements Bytestream
     private InBandBytestreamManager(XMPPConnection connection) {
         super(connection);
 
+        connection.addConnectionListener(new AbstractConnectionClosedListener() {
+            @Override
+            public void connectionTerminated() {
+                // reset internal status
+                InBandBytestreamManager.this.sessions.clear();
+                InBandBytestreamManager.this.ignoredBytestreamRequests.clear();
+            }
+        });
+
         // register bytestream open packet listener
         this.initiationListener = new InitiationListener(this);
         connection.registerIQRequestHandler(initiationListener);
@@ -453,19 +446,6 @@ public final class InBandBytestreamManager extends Manager implements Bytestream
         connection().sendStanza(error);
     }
 
-    /**
-     * Responses to the given IQ packet's sender with an XMPP error that an In-Band Bytestream open
-     * request is rejected because its block size is greater than the maximum allowed block size.
-     *
-     * @param request IQ stanza that should be answered with a resource-constraint error
-     * @throws NotConnectedException if the XMPP connection is not connected.
-     * @throws InterruptedException if the calling thread was interrupted.
-     */
-    protected void replyResourceConstraintPacket(IQ request) throws NotConnectedException, InterruptedException {
-        IQ error = IQ.createErrorResponse(request, StanzaError.Condition.resource_constraint);
-        connection().sendStanza(error);
-    }
-
     /**
      * Responses to the given IQ packet's sender with an XMPP error that an In-Band Bytestream
      * session could not be found.
@@ -539,30 +519,4 @@ public final class InBandBytestreamManager extends Manager implements Bytestream
         return ignoredBytestreamRequests;
     }
 
-    /**
-     * Disables the InBandBytestreamManager by removing its stanza listeners and resetting its
-     * internal status, which includes removing this instance from the managers map.
-     */
-    private void disableService() {
-        final XMPPConnection connection = connection();
-
-        // remove manager from static managers map
-        managers.remove(connection);
-
-        // remove all listeners registered by this manager
-        connection.unregisterIQRequestHandler(initiationListener);
-        connection.unregisterIQRequestHandler(dataListener);
-        connection.unregisterIQRequestHandler(closeListener);
-
-        // shutdown threads
-        this.initiationListener.shutdown();
-
-        // reset internal status
-        this.userListeners.clear();
-        this.allRequestListeners.clear();
-        this.sessions.clear();
-        this.ignoredBytestreamRequests.clear();
-
-    }
-
 }

smack-extensions/src/main/java/org/jivesoftware/smackx/bytestreams/ibb/InitiationListener.java

@@ -16,15 +16,9 @@
  */
 package org.jivesoftware.smackx.bytestreams.ibb;
 
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.logging.Level;
-import java.util.logging.Logger;
-
-import org.jivesoftware.smack.SmackException.NotConnectedException;
 import org.jivesoftware.smack.iqrequest.AbstractIqRequestHandler;
 import org.jivesoftware.smack.packet.IQ;
-import org.jivesoftware.smack.packet.Stanza;
+import org.jivesoftware.smack.packet.StanzaError;
 
 import org.jivesoftware.smackx.bytestreams.BytestreamListener;
 import org.jivesoftware.smackx.bytestreams.ibb.packet.Open;
@@ -44,14 +38,10 @@ import org.jivesoftware.smackx.filetransfer.StreamNegotiator;
  * @author Henning Staib
  */
 class InitiationListener extends AbstractIqRequestHandler {
-    private static final Logger LOGGER = Logger.getLogger(InitiationListener.class.getName());
 
     /* manager containing the listeners and the XMPP connection */
     private final InBandBytestreamManager manager;
 
-    /* executor service to process incoming requests concurrently */
-    private final ExecutorService initiationListenerExecutor;
-
     /**
      * Constructor.
      *
@@ -60,40 +50,29 @@ class InitiationListener extends AbstractIqRequestHandler {
     protected InitiationListener(InBandBytestreamManager manager) {
         super(Open.ELEMENT, Open.NAMESPACE, IQ.Type.set, Mode.async);
         this.manager = manager;
-        initiationListenerExecutor = Executors.newCachedThreadPool();
      }
 
     @Override
-    public IQ handleIQRequest(final IQ packet) {
+    public IQ handleIQRequest(final IQ iqRequest) {
-        initiationListenerExecutor.execute(new Runnable() {
+        Open ibbRequest = (Open) iqRequest;
-
-            @Override
-            public void run() {
-                try {
-                    processRequest(packet);
-                }
-                catch (InterruptedException | NotConnectedException e) {
-                    LOGGER.log(Level.WARNING, "proccessRequest", e);
-                }
-            }
-        });
-        return null;
-    }
-
-    private void processRequest(Stanza packet) throws NotConnectedException, InterruptedException {
-        Open ibbRequest = (Open) packet;
 
+        int blockSize = ibbRequest.getBlockSize();
+        int maximumBlockSize = manager.getMaximumBlockSize();
         // validate that block size is within allowed range
-        if (ibbRequest.getBlockSize() > this.manager.getMaximumBlockSize()) {
+        if (blockSize > maximumBlockSize) {
-            this.manager.replyResourceConstraintPacket(ibbRequest);
+            StanzaError error = StanzaError.getBuilder().setCondition(StanzaError.Condition.resource_constraint)
-            return;
+                            .setDescriptiveEnText("Requests block size of " + blockSize + " exceeds maximum block size of "
+                                                            + maximumBlockSize)
+                            .build();
+            return IQ.createErrorResponse(iqRequest, error);
         }
 
         StreamNegotiator.signal(ibbRequest.getFrom().toString() + '\t' + ibbRequest.getSessionID(), ibbRequest);
 
         // ignore request if in ignore list
-        if (this.manager.getIgnoredBytestreamRequests().remove(ibbRequest.getSessionID()))
+        if (this.manager.getIgnoredBytestreamRequests().remove(ibbRequest.getSessionID())) {
-            return;
+            return null;
+        }
 
         // build bytestream request from packet
         InBandBytestreamRequest request = new InBandBytestreamRequest(this.manager, ibbRequest);
@@ -102,7 +81,6 @@ class InitiationListener extends AbstractIqRequestHandler {
         BytestreamListener userListener = this.manager.getUserListener(ibbRequest.getFrom());
         if (userListener != null) {
             userListener.incomingBytestreamRequest(request);
-
         }
         else if (!this.manager.getAllRequestListeners().isEmpty()) {
             /*
@@ -111,21 +89,16 @@ class InitiationListener extends AbstractIqRequestHandler {
             for (BytestreamListener listener : this.manager.getAllRequestListeners()) {
                 listener.incomingBytestreamRequest(request);
             }
-
         }
         else {
-            /*
+            StanzaError error = StanzaError.getBuilder()
-             * if there is no listener for this initiation request, reply with reject message
+                            .setCondition(StanzaError.Condition.not_acceptable)
-             */
+                            .setDescriptiveEnText("No file-transfer listeners registered")
-            this.manager.replyRejectPacket(ibbRequest);
+                            .build();
+            return IQ.createErrorResponse(iqRequest, error);
         }
-    }
 
-    /**
+        return null;
-     * Shuts down the listeners executor service.
-     */
-    protected void shutdown() {
-        this.initiationListenerExecutor.shutdownNow();
     }
 
 }

smack-extensions/src/test/java/org/jivesoftware/smackx/bytestreams/ibb/InitiationListenerTest.java

@@ -83,23 +83,14 @@ public class InitiationListenerTest extends SmackTestSuite {
      */
     @Test
     public void shouldRespondWithError() throws Exception {
-
         // run the listener with the initiation packet
-        initiationListener.handleIQRequest(initBytestream);
+        IQ response = initiationListener.handleIQRequest(initBytestream);
-
-        // wait because packet is processed in an extra thread
-        Thread.sleep(200);
-
-        // capture reply to the In-Band Bytestream open request
-        ArgumentCaptor<IQ> argument = ArgumentCaptor.forClass(IQ.class);
-        verify(connection).sendStanza(argument.capture());
 
         // assert that reply is the correct error packet
-        assertEquals(initiatorJID, argument.getValue().getTo());
+        assertEquals(initiatorJID, response.getTo());
-        assertEquals(IQ.Type.error, argument.getValue().getType());
+        assertEquals(IQ.Type.error, response.getType());
         assertEquals(StanzaError.Condition.not_acceptable,
-                        argument.getValue().getError().getCondition());
+                        response.getError().getCondition());
-
     }
 
     /**
@@ -113,21 +104,13 @@ public class InitiationListenerTest extends SmackTestSuite {
         byteStreamManager.setMaximumBlockSize(1024);
 
         // run the listener with the initiation packet
-        initiationListener.handleIQRequest(initBytestream);
+        IQ response = initiationListener.handleIQRequest(initBytestream);
-
-        // wait because packet is processed in an extra thread
-        Thread.sleep(200);
-
-        // capture reply to the In-Band Bytestream open request
-        ArgumentCaptor<IQ> argument = ArgumentCaptor.forClass(IQ.class);
-        verify(connection).sendStanza(argument.capture());
 
         // assert that reply is the correct error packet
-        assertEquals(initiatorJID, argument.getValue().getTo());
+        assertEquals(initiatorJID, response.getTo());
-        assertEquals(IQ.Type.error, argument.getValue().getType());
+        assertEquals(IQ.Type.error, response.getType());
         assertEquals(StanzaError.Condition.resource_constraint,
-                        argument.getValue().getError().getCondition());
+                        response.getError().getCondition());
-
     }
 
     /**
@@ -199,24 +182,17 @@ public class InitiationListenerTest extends SmackTestSuite {
         byteStreamManager.addIncomingBytestreamListener(listener, JidCreate.from("other_" + initiatorJID));
 
         // run the listener with the initiation packet
-        initiationListener.handleIQRequest(initBytestream);
+        IQ response = initiationListener.handleIQRequest(initBytestream);
-
-        // wait because packet is processed in an extra thread
-        Thread.sleep(200);
 
         // assert listener is not called
         ArgumentCaptor<BytestreamRequest> byteStreamRequest = ArgumentCaptor.forClass(BytestreamRequest.class);
         verify(listener, never()).incomingBytestreamRequest(byteStreamRequest.capture());
 
-        // capture reply to the In-Band Bytestream open request
-        ArgumentCaptor<IQ> argument = ArgumentCaptor.forClass(IQ.class);
-        verify(connection).sendStanza(argument.capture());
-
         // assert that reply is the correct error packet
-        assertEquals(initiatorJID, argument.getValue().getTo());
+        assertEquals(initiatorJID, response.getTo());
-        assertEquals(IQ.Type.error, argument.getValue().getType());
+        assertEquals(IQ.Type.error, response.getType());
         assertEquals(StanzaError.Condition.not_acceptable,
-                        argument.getValue().getError().getCondition());
+                        response.getError().getCondition());
     }
 
     /**