1 files changed, 76 insertions, 0 deletions
diff --git a/java/java/broker/src/org/apache/qpid/server/queue/DeliveryManager.java b/java/java/broker/src/org/apache/qpid/server/queue/DeliveryManager.java
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+++ b/java/java/broker/src/org/apache/qpid/server/queue/DeliveryManager.java
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+/*
+ *
+ * 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.server.queue;
+
+import org.apache.qpid.AMQException;
+
+import java.util.concurrent.Executor;
+import java.util.List;
+
+interface DeliveryManager
+{
+    /**
+     * Determines whether there are queued messages. Sets _queueing to false if
+     * there are no queued messages. This needs to be atomic.
+     *
+     * @return true if there are queued messages
+     */
+    boolean hasQueuedMessages();
+
+    /**
+     * This method should not be used to determin if there are messages in the queue.
+     *
+     * @return int The number of messages in the queue
+     * @use hasQueuedMessages() for all controls relating to having messages on the queue.
+     */
+    int getQueueMessageCount();
+
+    /**
+     * Requests that the delivery manager start processing the queue asynchronously
+     * if there is work that can be done (i.e. there are messages queued up and
+     * subscribers that can receive them.
+     * <p/>
+     * This should be called when subscribers are added, but only after the consume-ok
+     * message has been returned as message delivery may start immediately. It should also
+     * be called after unsuspending a client.
+     * <p/>
+     *
+     * @param executor the executor on which the delivery should take place
+     */
+    void processAsync(Executor executor);
+
+    /**
+     * Handles message delivery. The delivery manager is always in one of two modes;
+     * it is either queueing messages for asynchronous delivery or delivering
+     * directly.
+     *
+     * @param name the name of the entity on whose behalf we are delivering the message
+     * @param msg  the message to deliver
+     * @throws org.apache.qpid.server.queue.FailedDequeueException if the message could not be dequeued
+     */
+    void deliver(String name, AMQMessage msg) throws FailedDequeueException;
+
+    void removeAMessageFromTop() throws AMQException;
+
+    void clearAllMessages() throws AMQException;
+
+    List<AMQMessage> getMessages();
+}