org.apache.rocketmq.example.simple.PullConsumer Maven / Gradle / Ivy
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* 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
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* http://www.apache.org/licenses/LICENSE-2.0
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* distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.rocketmq.example.simple;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import org.apache.rocketmq.client.consumer.DefaultMQPullConsumer;
import org.apache.rocketmq.client.consumer.PullResult;
import org.apache.rocketmq.client.consumer.store.ReadOffsetType;
import org.apache.rocketmq.client.exception.MQBrokerException;
import org.apache.rocketmq.client.exception.MQClientException;
import org.apache.rocketmq.common.ThreadFactoryImpl;
import org.apache.rocketmq.common.message.MessageExt;
import org.apache.rocketmq.common.message.MessageQueue;
import org.apache.rocketmq.remoting.exception.RemotingException;
@SuppressWarnings("deprecation")
public class PullConsumer {
public static void main(String[] args) throws MQClientException {
DefaultMQPullConsumer consumer = new DefaultMQPullConsumer("please_rename_unique_group_name_5");
consumer.setNamesrvAddr("127.0.0.1:9876");
Set topics = new HashSet<>();
//You would be better to register topics,It will use in rebalance when starting
topics.add("TopicTest");
consumer.setRegisterTopics(topics);
consumer.start();
ExecutorService executors = Executors.newFixedThreadPool(topics.size(), new ThreadFactoryImpl("PullConsumerThread"));
for (String topic : consumer.getRegisterTopics()) {
executors.execute(new Runnable() {
public void doSomething(List msgs) {
//do your business
}
@Override
public void run() {
while (true) {
try {
Set messageQueues = consumer.fetchMessageQueuesInBalance(topic);
if (messageQueues == null || messageQueues.isEmpty()) {
Thread.sleep(1000);
continue;
}
PullResult pullResult = null;
for (MessageQueue messageQueue : messageQueues) {
try {
long offset = this.consumeFromOffset(messageQueue);
pullResult = consumer.pull(messageQueue, "*", offset, 32);
switch (pullResult.getPullStatus()) {
case FOUND:
List msgs = pullResult.getMsgFoundList();
if (msgs != null && !msgs.isEmpty()) {
this.doSomething(msgs);
//update offset to local memory, eventually to broker
consumer.updateConsumeOffset(messageQueue, pullResult.getNextBeginOffset());
//print pull tps
this.incPullTPS(topic, pullResult.getMsgFoundList().size());
}
break;
case OFFSET_ILLEGAL:
consumer.updateConsumeOffset(messageQueue, pullResult.getNextBeginOffset());
break;
case NO_NEW_MSG:
Thread.sleep(1);
consumer.updateConsumeOffset(messageQueue, pullResult.getNextBeginOffset());
break;
case NO_MATCHED_MSG:
consumer.updateConsumeOffset(messageQueue, pullResult.getNextBeginOffset());
break;
default:
}
} catch (RemotingException e) {
e.printStackTrace();
} catch (MQBrokerException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
} catch (MQClientException e) {
//reblance error
e.printStackTrace();
} catch (InterruptedException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}
public long consumeFromOffset(MessageQueue messageQueue) throws MQClientException {
//-1 when started
long offset = consumer.getOffsetStore().readOffset(messageQueue, ReadOffsetType.READ_FROM_MEMORY);
if (offset < 0) {
//query from broker
offset = consumer.getOffsetStore().readOffset(messageQueue, ReadOffsetType.READ_FROM_STORE);
}
if (offset < 0) {
//first time start from last offset
offset = consumer.maxOffset(messageQueue);
}
//make sure
if (offset < 0) {
offset = 0;
}
return offset;
}
public void incPullTPS(String topic, int pullSize) {
consumer.getDefaultMQPullConsumerImpl().getRebalanceImpl().getmQClientFactory()
.getConsumerStatsManager().incPullTPS(consumer.getConsumerGroup(), topic, pullSize);
}
});
}
// executors.shutdown();
// consumer.shutdown();
}
}