/**
* 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.activemq.broker.region.policy;
import java.util.Iterator;
import java.util.List;
import org.apache.activemq.broker.ConnectionContext;
import org.apache.activemq.broker.region.MessageReference;
import org.apache.activemq.broker.region.SubscriptionRecovery;
import org.apache.activemq.broker.region.Topic;
import org.apache.activemq.command.ActiveMQDestination;
import org.apache.activemq.command.Message;
import org.apache.activemq.memory.list.DestinationBasedMessageList;
import org.apache.activemq.memory.list.MessageList;
import org.apache.activemq.memory.list.SimpleMessageList;
/**
* This implementation of {@link SubscriptionRecoveryPolicy} will keep a fixed
* amount of memory available in RAM for message history which is evicted in
* time order.
*
* @org.apache.xbean.XBean
* @version $Revision$
*/
public class FixedSizedSubscriptionRecoveryPolicy implements SubscriptionRecoveryPolicy {
private MessageList buffer;
private int maximumSize = 100 * 64 * 1024;
private boolean useSharedBuffer = true;
public SubscriptionRecoveryPolicy copy() {
FixedSizedSubscriptionRecoveryPolicy rc = new FixedSizedSubscriptionRecoveryPolicy();
rc.setMaximumSize(maximumSize);
rc.setUseSharedBuffer(useSharedBuffer);
return rc;
}
public boolean add(ConnectionContext context, MessageReference message) throws Exception {
buffer.add(message);
return true;
}
public void recover(ConnectionContext context, Topic topic, SubscriptionRecovery sub) throws Exception {
// Re-dispatch the messages from the buffer.
List copy = buffer.getMessages(sub.getActiveMQDestination());
if (!copy.isEmpty()) {
for (Iterator iter = copy.iterator(); iter.hasNext();) {
MessageReference node = (MessageReference)iter.next();
sub.addRecoveredMessage(context, node);
}
}
}
public void start() throws Exception {
buffer = createMessageList();
}
public void stop() throws Exception {
buffer.clear();
}
// Properties
// -------------------------------------------------------------------------
public MessageList getBuffer() {
return buffer;
}
public void setBuffer(MessageList buffer) {
this.buffer = buffer;
}
public int getMaximumSize() {
return maximumSize;
}
/**
* Sets the maximum amount of RAM in bytes that this buffer can hold in RAM
*/
public void setMaximumSize(int maximumSize) {
this.maximumSize = maximumSize;
}
public boolean isUseSharedBuffer() {
return useSharedBuffer;
}
public void setUseSharedBuffer(boolean useSharedBuffer) {
this.useSharedBuffer = useSharedBuffer;
}
public Message[] browse(ActiveMQDestination destination) throws Exception {
return buffer.browse(destination);
}
// Implementation methods
// -------------------------------------------------------------------------
protected MessageList createMessageList() {
if (useSharedBuffer) {
return new SimpleMessageList(maximumSize);
} else {
return new DestinationBasedMessageList(maximumSize);
}
}
}