1 files changed, 143 insertions, 0 deletions
diff --git a/trunk/qpid/java/client/src/main/java/org/apache/qpid/client/AMQQueueBrowser.java b/trunk/qpid/java/client/src/main/java/org/apache/qpid/client/AMQQueueBrowser.java
new file mode 100644
index 0000000000..d96544adf8
--- /dev/null
+++ b/trunk/qpid/java/client/src/main/java/org/apache/qpid/client/AMQQueueBrowser.java
@@ -0,0 +1,143 @@
+/*
+ *
+ * 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;
+
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.jms.IllegalStateException;
+import javax.jms.JMSException;
+import javax.jms.Message;
+import javax.jms.Queue;
+import javax.jms.QueueBrowser;
+import java.util.ArrayList;
+import java.util.Enumeration;
+import java.util.concurrent.atomic.AtomicBoolean;
+
+public class AMQQueueBrowser implements QueueBrowser
+{
+    private static final Logger _logger = LoggerFactory.getLogger(AMQQueueBrowser.class);
+
+    private AtomicBoolean _isClosed = new AtomicBoolean();
+    private final AMQSession _session;
+    private final AMQQueue _queue;
+    private final ArrayList<BasicMessageConsumer> _consumers = new ArrayList<BasicMessageConsumer>();
+    private final String _messageSelector;
+
+    AMQQueueBrowser(AMQSession session, AMQQueue queue, String messageSelector) throws JMSException
+    {
+        _session = session;
+        _queue = queue;
+        _messageSelector = ((messageSelector == null) || (messageSelector.trim().length() == 0)) ? null : messageSelector;
+        // Create Consumer to verify message selector.
+        BasicMessageConsumer consumer =
+                (BasicMessageConsumer) _session.createBrowserConsumer(_queue, _messageSelector, false);
+        // Close this consumer as we are not looking to consume only to establish that, at least for now,
+        // the QB can be created
+        consumer.close();
+    }
+
+    public Queue getQueue() throws JMSException
+    {
+        checkState();
+
+        return _queue;
+    }
+
+    private void checkState() throws JMSException
+    {
+        if (_isClosed.get())
+        {
+            throw new IllegalStateException("Queue Browser");
+        }
+
+        if (_session.isClosed())
+        {
+            throw new IllegalStateException("Session is closed");
+        }
+
+    }
+
+    public String getMessageSelector() throws JMSException
+    {
+
+        checkState();
+
+        return _messageSelector;
+    }
+
+    public Enumeration getEnumeration() throws JMSException
+    {
+        checkState();
+        final BasicMessageConsumer consumer =
+                (BasicMessageConsumer) _session.createBrowserConsumer(_queue, _messageSelector, false);
+
+        _consumers.add(consumer);
+
+        return new QueueBrowserEnumeration(consumer);
+    }
+
+    public void close() throws JMSException
+    {
+        for (BasicMessageConsumer consumer : _consumers)
+        {
+            consumer.close();
+        }
+
+        _consumers.clear();
+    }
+
+    private class QueueBrowserEnumeration implements Enumeration
+    {
+        Message _nextMessage;
+        private BasicMessageConsumer _consumer;
+
+        public QueueBrowserEnumeration(BasicMessageConsumer consumer) throws JMSException
+        {
+            _nextMessage = consumer == null ? null : consumer.receiveBrowse();
+            _logger.info("QB:created with first element:" + _nextMessage);
+            _consumer = consumer;
+        }
+
+        public boolean hasMoreElements()
+        {
+            _logger.info("QB:hasMoreElements:" + (_nextMessage != null));
+            return (_nextMessage != null);
+        }
+
+        public Object nextElement()
+        {
+            Message msg = _nextMessage;
+            try
+            {
+                _logger.info("QB:nextElement about to receive");
+                _nextMessage = _consumer.receiveBrowse();
+                _logger.info("QB:nextElement received:" + _nextMessage);
+            }
+            catch (JMSException e)
+            {
+                _logger.warn("Exception caught while queue browsing", e);
+                _nextMessage = null;
+            }
+            return msg;
+        }
+    }    
+}