RabbitMQ中的SimpleMessageListener

通過上文可以使用rabbitmq了，但是有這樣一個特殊需求，想不使用通用的配置，而是該隊列使用特殊的配置，那麼就可以使用SimpleMessageListener，來自定義消費者。

1.代碼實作

可以看到下文兩個方法配置了兩種應答方式，方法一為手動應答，方法二為自動應答。

1.手動應答SimpleMessageListener

如正規方式一樣，使用手動應答，需要在接收到消息後手動發送ack/nack。核心代碼如下：container.setAcknowledgeMode(AcknowledgeMode.MANUAL);

import org.springframework.amqp.core.AcknowledgeMode;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer;
import org.springframework.amqp.rabbit.listener.api.ChannelAwareMessageListener;
import org.springframework.amqp.support.ConsumerTagStrategy;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;

import com.alibaba.fastjson.JSONObject;
import com.rabbitmq.client.Channel;
import org.springframework.context.annotation.Configuration;


@Configuration
public class SimpleMessageListener {

    @Bean
    public SimpleMessageListenerContainer messageContainer(ConnectionFactory connectionFactory) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory);
        // 添加隊列 可以添加多個隊列
        container.setExposeListenerChannel(true);
        // 設定目前的消費者數量
        // container.setMaxConcurrentConsumers(5);
        container.setConcurrentConsumers(1);
        // 設定确認模式手工确認
        container.setAcknowledgeMode(AcknowledgeMode.MANUAL);
        container.setMessageListener(new ChannelAwareMessageListener() {
            @Override
            public void onMessage(Message message, Channel channel) throws Exception {
                byte[] body = message.getBody();
                System.out.println("1  receive msg : " + JSONObject.parseObject(new String(body)));
                // 确認消息成功消費，删除消息隊列中的消息，他跟上面貌似一樣
                channel.basicAck(message.getMessageProperties().getDeliveryTag(), true);
            }
        });
        return container;
    }

}      

2.自動應答SimpleMessageListener

該方法會直接應答，核心代碼如下：container.setAcknowledgeMode(AcknowledgeMode.AUTO);

import org.springframework.amqp.core.AcknowledgeMode;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.rabbit.connection.ConnectionFactory;
import org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer;
import org.springframework.amqp.rabbit.listener.api.ChannelAwareMessageListener;
import org.springframework.amqp.support.ConsumerTagStrategy;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.annotation.Bean;

import com.alibaba.fastjson.JSONObject;
import com.rabbitmq.client.Channel;
import org.springframework.context.annotation.Configuration;


@Configuration
public class SimpleMessageListener {

    @Bean
    public SimpleMessageListenerContainer messageContainer2(ConnectionFactory connectionFactory) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory);
        // 設定目前消費者數量
        container.setConcurrentConsumers(1);
        // 設定最大的消費者數量
        container.setMaxConcurrentConsumers(5);
        // 設定不要重回隊列
        container.setDefaultRequeueRejected(false);
        // 設定自動簽收
        container.setAcknowledgeMode(AcknowledgeMode.AUTO);
        // 設定消費端tag政策
        container.setConsumerTagStrategy(new ConsumerTagStrategy() {
            @Override
            public String createConsumerTag(String queue) {
                return queue + "_" + System.currentTimeMillis();
            }
        });
        // 設定監聽
        container.setMessageListener(new ChannelAwareMessageListener() {
            @Override
            public void onMessage(Message message, Channel channel) throws Exception {
                // 消息處理
                String msg = new String(message.getBody(), "UTF-8");
                System.out.println("---消費者---隊列名：" + message.getMessageProperties().getConsumerQueue() + "，消息：" + msg
                    + ",deliveryTag：" + message.getMessageProperties().getDeliveryTag());
                channel.basicAck(message.getMessageProperties().getDeliveryTag(), false);;
            }
        });
        return container;
    }
}