Springboot Rabbitmq 使用Jackson2JsonMessageConverter 消息传递后转对象

小程序：扫一扫查出行
【扫一扫了解最新限行尾号】
复制小程序

Springboot为了应对高并发，接入了消息队列Rabbitmq，第一版验证时使用简单消费队列：

//发送端
AbstractOrder order =new Order();
rabbitmqTemplate.convertAndSend(order);//消费端
public void recieved(AbstractOrder order){
log.info("recieved order:"+order);
//处理逻辑
}

第二版为了应对可能出行的处理失败，使用了Rabbitmq的Ack

下面是最终版代码：

//发送端
//把订单加入队列
public void convertAndSendOrder(AbstractOrder order){ rabbitmqTemplate.setMandatory(true);
rabbitmqTemplate.setConfirmCallback(confirmCallback);
rabbitmqTemplate.setReturnCallback(returnCallback);
//全局唯一不然ReturnCallback 无效
CorrelationData correlationData = new CorrelationData(UUID.randomUUID().toString()); rabbitmqTemplate.convertAndSend("exchange-order","rkey-orderadd",order,correlationData);
}

//消费端逻辑
@RabbitListener(bindings = {
@QueueBinding(value = @Queue(value = "queue-order"),
exchange = @Exchange(value = "exchange-order"),
key = "rkey-order")},containerFactory="rabbitListenerContainerFactory")
public void recieved(Message messageorigin, Channel channel){
log.info("recieved message:"+messageorigin);
boolean success = false; Order order =null; try {
Jackson2JsonMessageConverter jackson2JsonMessageConverter =new Jackson2JsonMessageConverter();
order = (Order)jackson2JsonMessageConverter.fromMessage(messageorigin); }catch (Exception e){
log.info("get order fromBytes message exception"+e.getMessage());
} //处理逻辑
//回调成功确认消息
if(success){
//成功确认消息
try{
channel.basicAck(messageorigin.getMessageProperties().getDeliveryTag(),false);
}catch (IOException e){
log.info("basicAck ex:"+e.getMessage());
try{
channel.basicAck(messageorigin.getMessageProperties().getDeliveryTag(),false);
}catch (IOException ee){
log.info("again basicAck ex:"+ee.getMessage()); }
}
}

注意：如果在received 中还像第一版直接转自定义对象，消息进程会报错

org.springframework.amqp.AmqpException: No method found for class com.xxx.Order

解决方案是使用Jackson2JsonMessageConverter 。在发送消息时，它会先将自定义的消息类序列化成json格式，再转成byte构造 Message

//发送设置Converter
@Bean
public RabbitTemplate rabbitTemplate(ConnectionFactory connectionFactory) {
RabbitTemplate template = new RabbitTemplate(connectionFactory);
template.setMessageConverter(new Jackson2JsonMessageConverter());
return template;
} @Bean
public SimpleRabbitListenerContainerFactory rabbitListenerContainerFactory(ConnectionFactory connectionFactory) {
SimpleRabbitListenerContainerFactory factory = new SimpleRabbitListenerContainerFactory();
factory.setConnectionFactory(connectionFactory);
factory.setMessageConverter(new Jackson2JsonMessageConverter());
return factory;
}//消费时指定Converter

@RabbitListener(bindings = {
@QueueBinding(value = @Queue(value = "queue-order"),
exchange = @Exchange(value = "exchange-order"),
key = "rkey-order")},containerFactory="rabbitListenerContainerFactory")

但是直接使用Jackson2JsonMessageConverter后，反序列化时要求发送的类和接受的类完全一样（字段，类名，包路径）。

查了下文档 https://docs.spring.io/spring-amqp/api/org/springframework/amqp/support/converter/Jackson2JsonMessageConverter.html

这里直接使用jackson2JsonMessageConverter.fromMessage的方法从Message拿出来。

ACK完成