QPID-6294 : [Java Client] Allow use of 0 prefetch in AMQP 0-8/9/9-1

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1648987 13f79535-47bb-0310-9956-ffa450edef68

3 files changed, 140 insertions, 18 deletions

diff --git a/qpid/java/client/src/main/java/org/apache/qpid/client/AMQSession_0_8.java b/qpid/java/client/src/main/java/org/apache/qpid/client/AMQSession_0_8.java
index d86a2739f2..bb0f0d9b13 100644
--- a/qpid/java/client/src/main/java/org/apache/qpid/client/AMQSession_0_8.java
+++ b/qpid/java/client/src/main/java/org/apache/qpid/client/AMQSession_0_8.java
@@ -824,12 +824,13 @@ public class AMQSession_0_8 extends AMQSession<BasicMessageConsumer_0_8, BasicMe
             throws AMQException, FailoverException
     {
         _currentPrefetch.set(0);
-        BasicQosBody basicQosBody = getProtocolHandler().getMethodRegistry().createBasicQosBody(sizePrefetch, messagePrefetch, false);
-
-        // todo send low water mark when protocol allows.
-        // todo Be aware of possible changes to parameter order as versions change.
-        getProtocolHandler().syncWrite(basicQosBody.generateFrame(getChannelId()), BasicQosOkBody.class);
+        if(messagePrefetch > 0 || sizePrefetch > 0)
+        {
+            BasicQosBody basicQosBody =
+                    getProtocolHandler().getMethodRegistry().createBasicQosBody(sizePrefetch, messagePrefetch, false);
 
+            getProtocolHandler().syncWrite(basicQosBody.generateFrame(getChannelId()), BasicQosOkBody.class);
+        }
     }
 
 
@@ -842,13 +843,17 @@ public class AMQSession_0_8 extends AMQSession<BasicMessageConsumer_0_8, BasicMe
                     public Boolean execute() throws AMQException, FailoverException
                     {
                         int currentPrefetch = _currentPrefetch.get();
-                        if (currentPrefetch >= getPrefetch())
+                        if (currentPrefetch >= getPrefetch() && getPrefetch() >= 0)
                         {
                             BasicQosBody basicQosBody = getProtocolHandler().getMethodRegistry()
                                     .createBasicQosBody(0, currentPrefetch + 1, false);
 
                             getProtocolHandler().syncWrite(basicQosBody.generateFrame(getChannelId()),
                                                            BasicQosOkBody.class);
+                            if(currentPrefetch == 0 && !isSuspended())
+                            {
+                                sendSuspendChannel(false);
+                            }
                             _creditChanged.set(true);
                             return true;
                         }
@@ -863,8 +868,7 @@ public class AMQSession_0_8 extends AMQSession<BasicMessageConsumer_0_8, BasicMe
 
     protected void reduceCreditAfterAcknowledge() throws AMQException
     {
-        int acknowledgeMode = getAcknowledgeMode();
-        boolean manageCredit = acknowledgeMode == javax.jms.Session.CLIENT_ACKNOWLEDGE || acknowledgeMode == javax.jms.Session.SESSION_TRANSACTED;
+        boolean manageCredit = isManagingCredit();
 
         if(manageCredit && _creditChanged.compareAndSet(true,false))
         {
@@ -873,18 +877,40 @@ public class AMQSession_0_8 extends AMQSession<BasicMessageConsumer_0_8, BasicMe
                     {
                         public Void execute() throws AMQException, FailoverException
                         {
-                            BasicQosBody basicQosBody =
-                                    getProtocolHandler().getMethodRegistry()
-                                            .createBasicQosBody(0, getPrefetch(), false);
+                            int prefetch = getPrefetch();
+                            if(prefetch == 0)
+                            {
+                                sendSuspendChannel(true);
+                            }
+                            else
+                            {
+                                BasicQosBody basicQosBody =
+                                        getProtocolHandler().getMethodRegistry()
+                                                .createBasicQosBody(0, prefetch == -1 ? 0 : prefetch, false);
 
-                            getProtocolHandler().syncWrite(basicQosBody.generateFrame(getChannelId()),
-                                                           BasicQosOkBody.class);
+                                getProtocolHandler().syncWrite(basicQosBody.generateFrame(getChannelId()),
+                                                               BasicQosOkBody.class);
+                            }
                             return null;
                         }
                     }, getProtocolHandler().getConnection()).execute();
         }
     }
 
+    protected void reduceCreditInPostDeliver()
+    {
+        int acknowledgeMode = getAcknowledgeMode();
+        boolean manageCredit = (acknowledgeMode == AUTO_ACKNOWLEDGE || acknowledgeMode == DUPS_OK_ACKNOWLEDGE) && getPrefetch() == 0;
+
+        if(manageCredit && _creditChanged.compareAndSet(true,false))
+        {
+            ChannelFlowBody body = getMethodRegistry().createChannelFlowBody(false);
+            AMQFrame channelFlowFrame = body.generateFrame(getChannelId());
+            getProtocolHandler().writeFrame(channelFlowFrame, true);
+        }
+    }
+
+
     protected void updateCurrentPrefetch(int delta)
     {
         _currentPrefetch.addAndGet(delta);
@@ -1414,6 +1440,15 @@ public class AMQSession_0_8 extends AMQSession<BasicMessageConsumer_0_8, BasicMe
         }
     }
 
+    boolean isManagingCredit()
+    {
+        int acknowledgeMode = getAcknowledgeMode();
+        return acknowledgeMode == CLIENT_ACKNOWLEDGE
+               || acknowledgeMode == SESSION_TRANSACTED
+               || ((acknowledgeMode == AUTO_ACKNOWLEDGE || acknowledgeMode == DUPS_OK_ACKNOWLEDGE) && getPrefetch() == 0);
+    }
+
+
     public boolean isFlowBlocked()
     {
         synchronized (_flowControl)
diff --git a/qpid/java/client/src/main/java/org/apache/qpid/client/BasicMessageConsumer_0_8.java b/qpid/java/client/src/main/java/org/apache/qpid/client/BasicMessageConsumer_0_8.java
index 6718121e6b..3cc50512ed 100644
--- a/qpid/java/client/src/main/java/org/apache/qpid/client/BasicMessageConsumer_0_8.java
+++ b/qpid/java/client/src/main/java/org/apache/qpid/client/BasicMessageConsumer_0_8.java
@@ -22,7 +22,6 @@ package org.apache.qpid.client;
 
 import javax.jms.JMSException;
 import javax.jms.Message;
-import javax.jms.Session;
 
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -170,8 +169,7 @@ public class BasicMessageConsumer_0_8 extends BasicMessageConsumer<UnprocessedMe
     @Override
     public Message receive(final long l) throws JMSException
     {
-        int acknowledgeMode = getSession().getAcknowledgeMode();
-        boolean manageCredit = acknowledgeMode == Session.CLIENT_ACKNOWLEDGE || acknowledgeMode == Session.SESSION_TRANSACTED;
+        boolean manageCredit = getSession().isManagingCredit();
         boolean creditModified = false;
         try
         {
@@ -199,8 +197,7 @@ public class BasicMessageConsumer_0_8 extends BasicMessageConsumer<UnprocessedMe
     @Override
     public Message receiveNoWait() throws JMSException
     {
-        int acknowledgeMode = getSession().getAcknowledgeMode();
-        boolean manageCredit = acknowledgeMode == Session.CLIENT_ACKNOWLEDGE || acknowledgeMode == Session.SESSION_TRANSACTED;
+        boolean manageCredit = getSession().isManagingCredit();
         boolean creditModified = false;
         try
         {
@@ -228,4 +225,11 @@ public class BasicMessageConsumer_0_8 extends BasicMessageConsumer<UnprocessedMe
             throw new JMSAMQException(e);
         }
     }
+
+
+    void postDeliver(AbstractJMSMessage msg)
+    {
+        getSession().reduceCreditInPostDeliver();
+        super.postDeliver(msg);
+    }
 }
diff --git a/qpid/java/systests/src/test/java/org/apache/qpid/systest/prefetch/ZeroPrefetchTest.java b/qpid/java/systests/src/test/java/org/apache/qpid/systest/prefetch/ZeroPrefetchTest.java
new file mode 100644
index 0000000000..6a9fa0175a
--- /dev/null
+++ b/qpid/java/systests/src/test/java/org/apache/qpid/systest/prefetch/ZeroPrefetchTest.java
@@ -0,0 +1,83 @@
+/*
+ *
+ * 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.systest.prefetch;
+
+import java.util.UUID;
+
+import javax.jms.Connection;
+import javax.jms.Message;
+import javax.jms.MessageConsumer;
+import javax.jms.MessageProducer;
+import javax.jms.Queue;
+import javax.jms.Session;
+
+import org.apache.qpid.configuration.ClientProperties;
+import org.apache.qpid.test.utils.QpidBrokerTestCase;
+
+public class ZeroPrefetchTest extends QpidBrokerTestCase
+{
+
+    private static final String TEST_PROPERTY_NAME = "testProp";
+
+    // send two messages to the queue, consume and acknowledge one message on connection 1
+    // create a second connection and attempt to consume the second message - this will only be possible
+    // if the first connection has no prefetch
+    public void testZeroPrefetch() throws Exception
+    {
+        setTestClientSystemProperty(ClientProperties.MAX_PREFETCH_PROP_NAME, "0");
+        Connection prefetch1Connection = getConnection();
+
+        prefetch1Connection.start();
+
+        final Session prefetch1session = prefetch1Connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+        Queue queue = prefetch1session.createQueue(getTestQueueName());
+        MessageConsumer prefetch1consumer = prefetch1session.createConsumer(queue);
+
+
+        Session producerSession = prefetch1Connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+        MessageProducer producer = producerSession.createProducer(queue);
+        Message firstMessage = producerSession.createMessage();
+        String firstPropertyValue = UUID.randomUUID().toString();
+        firstMessage.setStringProperty(TEST_PROPERTY_NAME, firstPropertyValue);
+        producer.send(firstMessage);
+
+        Message secondMessage = producerSession.createMessage();
+        String secondPropertyValue = UUID.randomUUID().toString();
+        secondMessage.setStringProperty(TEST_PROPERTY_NAME, secondPropertyValue);
+        producer.send(secondMessage);
+
+
+        Message receivedMessage = prefetch1consumer.receive(2000l);
+        assertNotNull("First message was not received", receivedMessage);
+        assertEquals("Message property was not as expected", firstPropertyValue, receivedMessage.getStringProperty(TEST_PROPERTY_NAME));
+
+        Connection prefetch2Connection = getConnection();
+
+        prefetch2Connection.start();
+        final Session prefetch2session = prefetch2Connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
+        MessageConsumer prefetch2consumer = prefetch2session.createConsumer(queue);
+
+        receivedMessage = prefetch2consumer.receive(2000l);
+        assertNotNull("Second message was not received", receivedMessage);
+        assertEquals("Message property was not as expected", secondPropertyValue, receivedMessage.getStringProperty(TEST_PROPERTY_NAME));
+
+    }
+}