/**
* Copyright (C) 2010-2013 Alibaba Group Holding Limited
*
* Licensed 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 com.alibaba.rocketmq.client.impl.consumer;
import java.nio.ByteBuffer;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.atomic.AtomicLong;
import com.alibaba.rocketmq.client.VirtualEnvUtil;
import com.alibaba.rocketmq.client.consumer.PullCallback;
import com.alibaba.rocketmq.client.consumer.PullResult;
import com.alibaba.rocketmq.client.consumer.PullStatus;
import com.alibaba.rocketmq.client.exception.MQBrokerException;
import com.alibaba.rocketmq.client.exception.MQClientException;
import com.alibaba.rocketmq.client.impl.CommunicationMode;
import com.alibaba.rocketmq.client.impl.FindBrokerResult;
import com.alibaba.rocketmq.client.impl.factory.MQClientFactory;
import com.alibaba.rocketmq.common.MixAll;
import com.alibaba.rocketmq.common.UtilAll;
import com.alibaba.rocketmq.common.message.MessageConst;
import com.alibaba.rocketmq.common.message.MessageDecoder;
import com.alibaba.rocketmq.common.message.MessageExt;
import com.alibaba.rocketmq.common.message.MessageQueue;
import com.alibaba.rocketmq.common.protocol.header.PullMessageRequestHeader;
import com.alibaba.rocketmq.common.protocol.heartbeat.SubscriptionData;
import com.alibaba.rocketmq.common.sysflag.PullSysFlag;
import com.alibaba.rocketmq.remoting.exception.RemotingException;
/**
* 对Pull接口进行进一步的封装
*
* @author shijia.wxr<vintage.wang@gmail.com>
* @since 2013-7-24
*/
public class PullAPIWrapper {
private ConcurrentHashMap<MessageQueue, AtomicLong/* brokerId */> pullFromWhichNodeTable =
new ConcurrentHashMap<MessageQueue, AtomicLong>(32);
private final MQClientFactory mQClientFactory;
private final String consumerGroup;
public PullAPIWrapper(MQClientFactory mQClientFactory, String consumerGroup) {
this.mQClientFactory = mQClientFactory;
this.consumerGroup = consumerGroup;
}
public void updatePullFromWhichNode(final MessageQueue mq, final long brokerId) {
AtomicLong suggest = this.pullFromWhichNodeTable.get(mq);
if (null == suggest) {
this.pullFromWhichNodeTable.put(mq, new AtomicLong(brokerId));
}
else {
suggest.set(brokerId);
}
}
/**
* 对拉取结果进行处理，主要是消息反序列化
*
* @param mq
* @param pullResult
* @param subscriptionData
* @param projectGroupPrefix
* 虚拟环境projectGroupPrefix，不存在可设置为 null
* @return
*/
public PullResult processPullResult(final MessageQueue mq, final PullResult pullResult,
final SubscriptionData subscriptionData) {
final String projectGroupPrefix = this.mQClientFactory.getMQClientAPIImpl().getProjectGroupPrefix();
PullResultExt pullResultExt = (PullResultExt) pullResult;
this.updatePullFromWhichNode(mq, pullResultExt.getSuggestWhichBrokerId());
if (PullStatus.FOUND == pullResult.getPullStatus()) {
ByteBuffer byteBuffer = ByteBuffer.wrap(pullResultExt.getMessageBinary());
List<MessageExt> msgList = MessageDecoder.decodes(byteBuffer);
// 消息再次过滤
List<MessageExt> msgListFilterAgain = msgList;
if (!subscriptionData.getTagsSet().isEmpty()) {
msgListFilterAgain = new ArrayList<MessageExt>(msgList.size());
for (MessageExt msg : msgList) {
if (msg.getTags() != null) {
if (subscriptionData.getTagsSet().contains(msg.getTags())) {
msgListFilterAgain.add(msg);
}
}
}
}
// 清除虚拟运行环境相关的projectGroupPrefix
if (!UtilAll.isBlank(projectGroupPrefix)) {
subscriptionData.setTopic(VirtualEnvUtil.clearProjectGroup(subscriptionData.getTopic(),
projectGroupPrefix));
mq.setTopic(VirtualEnvUtil.clearProjectGroup(mq.getTopic(), projectGroupPrefix));
for (MessageExt msg : msgListFilterAgain) {
msg.setTopic(VirtualEnvUtil.clearProjectGroup(msg.getTopic(), projectGroupPrefix));
// 消息中放入队列的最大最小Offset，方便应用来感知消息堆积程度
msg.putProperty(MessageConst.PROPERTY_MIN_OFFSET,
Long.toString(pullResult.getMinOffset()));
msg.putProperty(MessageConst.PROPERTY_MAX_OFFSET,
Long.toString(pullResult.getMaxOffset()));
}
}
else {
// 消息中放入队列的最大最小Offset，方便应用来感知消息堆积程度
for (MessageExt msg : msgListFilterAgain) {
msg.putProperty(MessageConst.PROPERTY_MIN_OFFSET,
Long.toString(pullResult.getMinOffset()));
msg.putProperty(MessageConst.PROPERTY_MAX_OFFSET,
Long.toString(pullResult.getMaxOffset()));
}
}
pullResultExt.setMsgFoundList(msgListFilterAgain);
}
// 令GC释放内存
pullResultExt.setMessageBinary(null);
return pullResult;
}
/**
* 每个队列都应该有相应的变量来保存从哪个服务器拉
*/
public long recalculatePullFromWhichNode(final MessageQueue mq) {
AtomicLong suggest = this.pullFromWhichNodeTable.get(mq);
if (suggest != null) {
return suggest.get();
}
return MixAll.MASTER_ID;
}
public PullResult pullKernelImpl(//
final MessageQueue mq,// 1
final String subExpression,// 2
final long subVersion,// 3
final long offset,// 4
final int maxNums,// 5
final int sysFlag,// 6
final long commitOffset,// 7
final long brokerSuspendMaxTimeMillis,// 8
final long timeoutMillis,// 9
final CommunicationMode communicationMode,// 10
final PullCallback pullCallback// 11
) throws MQClientException, RemotingException, MQBrokerException, InterruptedException {
FindBrokerResult findBrokerResult =
this.mQClientFactory.findBrokerAddressInSubscribe(mq.getBrokerName(),
this.recalculatePullFromWhichNode(mq), false);
if (null == findBrokerResult) {
// TODO 此处可能对Name Server压力过大，需要调优
this.mQClientFactory.updateTopicRouteInfoFromNameServer(mq.getTopic());
findBrokerResult =
this.mQClientFactory.findBrokerAddressInSubscribe(mq.getBrokerName(),
this.recalculatePullFromWhichNode(mq), false);
}
if (findBrokerResult != null) {
int sysFlagInner = sysFlag;
// Slave不允许实时提交消费进度，可以定时提交
if (findBrokerResult.isSlave()) {
sysFlagInner = PullSysFlag.clearCommitOffsetFlag(sysFlagInner);
}
PullMessageRequestHeader requestHeader = new PullMessageRequestHeader();
requestHeader.setConsumerGroup(this.consumerGroup);
requestHeader.setTopic(mq.getTopic());
requestHeader.setQueueId(mq.getQueueId());
requestHeader.setQueueOffset(offset);
requestHeader.setMaxMsgNums(maxNums);
requestHeader.setSysFlag(sysFlagInner);
requestHeader.setCommitOffset(commitOffset);
requestHeader.setSuspendTimeoutMillis(brokerSuspendMaxTimeMillis);
requestHeader.setSubscription(subExpression);
requestHeader.setSubVersion(subVersion);
PullResult pullResult = this.mQClientFactory.getMQClientAPIImpl().pullMessage(//
findBrokerResult.getBrokerAddr(),//
requestHeader,//
timeoutMillis,//
communicationMode,//
pullCallback);
return pullResult;
}
throw new MQClientException("The broker[" + mq.getBrokerName() + "] not exist", null);
}
}