消息模板-RabbitTemplate

RabbitTemplate是我们在与SpringAMQP整合的时候进行发送消息的关键类
该类提供了丰富的发送消息的方法，包括可靠性消息投递、回调监听消息接口ConfirmCallback、返回值确认接口
ReturnCallback等等同样我们需要注入到Spring容器中，然后直接使用。
在与spring整合时需要实例化，但是在与Springboot整合时，只需要添加配置文件即可

首先将其注入到bean里面：

    @Bean
    public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory) {
        RabbitTemplate rabbitTemplate = new RabbitTemplate(connectionFactory);
        return rabbitTemplate;
    }

然后在其他类引用：

package com.dwz.spring;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.amqp.AmqpException;
import org.springframework.amqp.core.Message;
import org.springframework.amqp.core.MessagePostProcessor;
import org.springframework.amqp.core.MessageProperties;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringRunner;

@RunWith(SpringRunner.class)
@SpringBootTest
public class TestDwz {
    @Autowired
    private RabbitTemplate rabbitTemplate;
    
    @Test
    public void testMessage01() {
        MessageProperties messageProperties = new MessageProperties();
        messageProperties.getHeaders().put("desc", "信息描述。。。");
        messageProperties.getHeaders().put("type", "自定义消息类型。。。");
        Message message = new Message("Hello RabbitMQ!".getBytes(), messageProperties);
        
        rabbitTemplate.convertAndSend("topic001", "spring.amqp", message, new MessagePostProcessor() {
            
            @Override
            public Message postProcessMessage(Message message) throws AmqpException {
                System.out.println("----添加额外的设置----");
                message.getMessageProperties().getHeaders().put("desc", "额外修改的信息描述");
                message.getMessageProperties().getHeaders().put("attr", "额外新加的属性");
                return message;
            }
        });
    }
    
    @Test
    public void testMessage02() {
        //创建消息
        MessageProperties messageProperties = new MessageProperties();
        messageProperties.setContentType("text/plain");
        Message message = new Message("spring 消息".getBytes(), messageProperties);
        rabbitTemplate.send("topic001", "spring.abc", message);
        
        rabbitTemplate.convertAndSend("topic001", "spring.amqp", "hello object message send!");
    }
}