1 files changed, 115 insertions, 0 deletions
diff --git a/qpid/java/client/src/main/java/org/apache/qpid/client/protocol/ProtocolBufferMonitorFilter.java b/qpid/java/client/src/main/java/org/apache/qpid/client/protocol/ProtocolBufferMonitorFilter.java
new file mode 100644
index 0000000000..bbd0a7b144
--- /dev/null
+++ b/qpid/java/client/src/main/java/org/apache/qpid/client/protocol/ProtocolBufferMonitorFilter.java
@@ -0,0 +1,115 @@
+/*
+ *
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ *
+ */
+package org.apache.qpid.client.protocol;
+
+import org.apache.mina.common.IoFilterAdapter;
+import org.apache.mina.common.IoSession;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * A MINA filter that monitors the numbers of messages pending to be sent by MINA. It outputs a message
+ * when a threshold has been exceeded, and has a frequency configuration so that messages are not output
+ * too often.
+ *
+ */
+public class ProtocolBufferMonitorFilter extends IoFilterAdapter
+{
+    private static final Logger _logger = LoggerFactory.getLogger(ProtocolBufferMonitorFilter.class);
+
+    public static final long DEFAULT_FREQUENCY = 5000;
+
+    public static final int DEFAULT_THRESHOLD = 3000;
+
+    private int _bufferedMessages = 0;
+
+    private int _threshold;
+
+    private long _lastMessageOutputTime;
+
+    private long _outputFrequencyInMillis;
+
+    public ProtocolBufferMonitorFilter()
+    {
+        _threshold = DEFAULT_THRESHOLD;
+        _outputFrequencyInMillis = DEFAULT_FREQUENCY;
+    }
+
+    public ProtocolBufferMonitorFilter(int threshold, long frequency)
+    {
+        _threshold = threshold;
+        _outputFrequencyInMillis = frequency;
+    }
+
+    public void messageReceived(NextFilter nextFilter, IoSession session, Object message) throws Exception
+    {
+        _bufferedMessages++;
+        if (_bufferedMessages > _threshold)
+        {
+            long now = System.currentTimeMillis();
+            if ((now - _lastMessageOutputTime) > _outputFrequencyInMillis)
+            {
+                _logger.warn("Protocol message buffer exceeded threshold of " + _threshold + ". Current backlog: "
+                    + _bufferedMessages);
+                _lastMessageOutputTime = now;
+            }
+        }
+
+        nextFilter.messageReceived(session, message);
+    }
+
+    public void messageSent(NextFilter nextFilter, IoSession session, Object message) throws Exception
+    {
+        _bufferedMessages--;
+        nextFilter.messageSent(session, message);
+    }
+
+    public int getBufferedMessages()
+    {
+        return _bufferedMessages;
+    }
+
+    public int getThreshold()
+    {
+        return _threshold;
+    }
+
+    public void setThreshold(int threshold)
+    {
+        _threshold = threshold;
+    }
+
+    public long getOutputFrequencyInMillis()
+    {
+        return _outputFrequencyInMillis;
+    }
+
+    public void setOutputFrequencyInMillis(long outputFrequencyInMillis)
+    {
+        _outputFrequencyInMillis = outputFrequencyInMillis;
+    }
+
+    public long getLastMessageOutputTime()
+    {
+        return _lastMessageOutputTime;
+    }
+}