RocketMQ-Filer

一、搭建RocketMQ集群

　　我搭建的是2-master no slave模式，所以在${rocketmq}/conf/2m-noslave/下的 brokder-*.properties 中添加 filterServerNums=1

二、依次启动namesrv和broker

　　在broker-*.properties中配置了filterServerNums=1后当你启动broker后，会自动启动filter

三、代码部分

　　3.1 Producer部分

package org.hope.lee.filter;

import com.alibaba.rocketmq.client.exception.MQClientException;
import com.alibaba.rocketmq.client.producer.DefaultMQProducer;
import com.alibaba.rocketmq.client.producer.SendResult;
import com.alibaba.rocketmq.common.message.Message;

public class FilterProducer {
    public static void main(String[] args) throws MQClientException {
        String group_name = "filter_producer";
        DefaultMQProducer producer = new DefaultMQProducer(group_name);
        producer.setNamesrvAddr("xxx.xxx.xx.176:9876;xxx.xx.xx.165:9876");
        producer.start();
        try {
            for (int i = 0; i < 100; i++) {
                Message msg = new Message("TopicFilter7",// topic
                    "TagA",// tag
                    "OrderID001",// key
                    ("Hello MetaQ" + i).getBytes());// body
                msg.putUserProperty("SequenceId", String.valueOf(i));
                SendResult sendResult = producer.send(msg);
                System.out.println(sendResult);
            }
        }
        catch (Exception e) {
            e.printStackTrace();
        }
        producer.shutdown();
    }
}

　　3.2 Customer部分

package org.hope.lee.filter;

import java.io.UnsupportedEncodingException;
import java.util.List;

import com.alibaba.rocketmq.client.consumer.DefaultMQPushConsumer;
import com.alibaba.rocketmq.client.consumer.listener.ConsumeConcurrentlyContext;
import com.alibaba.rocketmq.client.consumer.listener.ConsumeConcurrentlyStatus;
import com.alibaba.rocketmq.client.consumer.listener.MessageListenerConcurrently;
import com.alibaba.rocketmq.client.exception.MQClientException;
import com.alibaba.rocketmq.common.MixAll;
import com.alibaba.rocketmq.common.message.MessageExt;

public class FilterCustomer {
    public static void main(String[] args) throws MQClientException {
        String group_name = "filter_consumer";
        DefaultMQPushConsumer consumer = new DefaultMQPushConsumer(group_name);
        consumer.setNamesrvAddr("xxx.xxx.xx.176:9876;xxx.xxx.xx.165:9876");
        // 使用Java代码，在服务器做消息过滤
        String filterCode = MixAll.file2String("E:\\code-on-oschina\\hzjsd1108sohu\\RocketMQ-learn\\rocketmq-api\\src\\main\\java\\org\\hope\\lee\\filter\\MessageFilterImpl.java");
        System.out.println(filterCode);
        consumer.subscribe("TopicFilter7", "org.hope.lee.filter.MessageFilterImpl", filterCode);
        consumer.registerMessageListener(new MessageListenerConcurrently() {
            @Override
            public ConsumeConcurrentlyStatus consumeMessage(List<MessageExt> msgs,
                    ConsumeConcurrentlyContext context) {
                //System.out.println(Thread.currentThread().getName() + " Receive New Messages: " + msgs);
                try {
                    System.out.println(new String(msgs.get(0).getBody(),"utf-8"));
                } catch (UnsupportedEncodingException e) {
                    e.printStackTrace();
                }
                return ConsumeConcurrentlyStatus.CONSUME_SUCCESS;
            }
        });
        consumer.start();
        System.out.println("Consumer Started.");
    }
}

　　3.3 实现MessageFilter接口

　　　　注意：这个类中不能有任何的中文，包括注释中也不能有。否则在Customer启动的时候是找不到这个文件的。

package org.hope.lee.filter;

import com.alibaba.rocketmq.common.filter.MessageFilter;
import com.alibaba.rocketmq.common.message.MessageExt;

public class MessageFilterImpl implements MessageFilter {

    @Override
    public boolean match(MessageExt msg) {
        // NO Chinese
        System.out.println("-------------");
        String property = msg.getUserProperty("SequenceId");
        System.out.println("---------" + property);
        if (property != null) {
            int id = Integer.parseInt(property);
            if((id % 2) == 0) {
            //if ((id % 3) == 0 && (id > 10)) {
                return true;
            }
        }

        return false;
    }

}

四、测试：

　　4.1 运行Customer端

　　4.2运行Producer端

https://gitee.com/huayicompany/RocketMQ-learn/tree/master/rocketmq-api

参考：

[1] 白贺翔博客，https://www.cnblogs.com/baihexiang/articles/5307073.html

[2] 考拉哥博客，http://lifestack.cn/archives/371.html