MQ

MQ介绍：消息队列中间件 （MQ中间件）
作用：异步处理，应用解耦，流量削峰，消息通知
1.Spring整合rabbitmq
生产者；
1. 引入依赖spring-boot-start-amqp
2. 配置rabbitmq连接参数
3. 注入RabbitTemplate发送消息
消费者：
1.引入依赖spring-boot-start-amqp
2. 配置rabbitmq连接参数
3. 配置监听 @RabbitListener 注解
2.队列交换机绑定
1@Configuration + @Bean
java
@Configuration
public class FanoutConfig {
/
声明交换机
@return Fanout类型交换机
*/
@Bean
public FanoutExchange fanoutExchange(){
return new FanoutExchange(“itcast.fanout”);
}
/
第1个队列
/
@Bean
public Queue fanoutQueue1(){
return new Queue(“fanout.queue1”);
}
/
绑定队列和交换机
/
@Bean
public Binding bindingQueue1(Queue fanoutQueue1, FanoutExchange fanoutExchange){
return BindingBuilder.bind(fanoutQueue1).to(fanoutExchange);
}
/
第2个队列
/
@Bean
public Queue fanoutQueue2(){
return new Queue(“fanout.queue2”);
}
/
绑定队列和交换机
/
@Bean
public Binding bindingQueue2(Queue fanoutQueue2, FanoutExchange fanoutExchange){
return BindingBuilder.bind(fanoutQueue2).to(fanoutExchange);
}
}
2.@RabbitListener中通过注解声明java
@RabbitListener(bindings = @QueueBinding(
value = @Queue(name = “topic.queue1”),
exchange = @Exchange(name = “itcast.topic”, type = ExchangeTypes.TOPIC),
key = “china.#”
))
public void listenTopicQueue1(String msg){
System.out.println(“消费者接收到topic.queue1的消息：【” + msg + “】”);
}

@RabbitListener(bindings = @QueueBinding(
value = @Queue(name = “topic.queue2”),
exchange = @Exchange(name = “itcast.topic”, type = ExchangeTypes.TOPIC),
key = “#.news”
))
public void listenTopicQueue2(String msg){
System.out.println(“消费者接收到topic.queue2的消息：【” + msg + “】”);
}
3.消息转换器
Spring通过MessageConverter实现消息的序列化反序列化
java
@Bean
public MessageConverter jsonMessageConverter(){
return new Jackson2JsonMessageConverter();
}
体积大，性能差 默认使用JDK序列化
4.4种交换器类型
Direct Exchange Fanout Exchange Topic Exchange Headers Exchange(性能差，不常用)