java - Spring Boot RabbitMQ 接收器 Jackson 反序列化为 POJO

Question

我有一个 Spring Boot 项目，我正在尝试与 RabbitMQ 服务器集成，以便我可以向队列发布消息并从队列读取消息。

这是我的rabbitmq配置(编辑后仅显示相关详细信息):

@Configuration
@ConfigurationProperties(prefix="rabbit")
public class RabbitConfig {
    private String queue;

    @Bean
    Queue queue() {
        return new Queue(queue, durable);
    }

    @Bean
    public MessageConverter jsonMessageConverter(){
        return new Jackson2JsonMessageConverter();
    }

    @Bean
    SimpleMessageListenerContainer container(ConnectionFactory connectionFactory, Queue queue,
                                             MessageListenerAdapter listenerAdapter, MessageConverter messageConverter) {
        SimpleMessageListenerContainer container = new SimpleMessageListenerContainer(connectionFactory);
        container.setQueues(queue);
        container.setMessageListener(listenerAdapter);
        container.setMessageConverter(messageConverter);
        return container;
    }

    @Bean
    MessageListenerAdapter listenerAdapter(Receiver receiver) {
        return new MessageListenerAdapter(receiver);
    }

    public void setQueue(String queue) {
        this.queue = queue;
    }
}

这是我的接收器类:

public interface Receiver {
    void handleMessage(FooA message);
}

@Component
public class RabbitReceiver implements Receiver {
    @Override
    public void handleMessage(FooA message) {
        System.out.println(message);
    }
}

还有我的pojo:

public class FooA {}
    private double num;
    private Map<String, String> map = new HashMap();

    public FooA() {
    }

    public FooA(double num, Map<String, String> map) {
        this.num = num;
        this.map = map;
    }

    public int getnum() {
        return num;
    }

    public Map<String, String> getMap() {
        return map;
    }
}

我成功地将 FooA 消息对象发布到队列。这是队列中的样子:

[
    {
        "payload_bytes": 41,
        "redelivered": false,
        "exchange": "amq.fanout",
        "routing_key": "",
        "message_count": 0,
        "properties": {
            "priority": 0,
            "delivery_mode": 2,
            "headers": {
                "__TypeId__": "com.test.FooA"
            },
            "content_encoding": "UTF-8",
            "content_type": "application/json"
        },
        "payload": "{\"num\":1.2,\"map\":{}}",
        "payload_encoding": "string"
    }
]

但是当我尝试从队列中读取时，我收到此错误:

org.springframework.amqp.rabbit.listener.exception.ListenerExecutionFailedException: Failed to invoke target method 'handleMessage' with argument type = [class [B], value = [{[B@75a7bfc9}]
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.invokeListenerMethod(MessageListenerAdapter.java:408) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.onMessage(MessageListenerAdapter.java:298) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.doInvokeListener(AbstractMessageListenerContainer.java:822) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.invokeListener(AbstractMessageListenerContainer.java:745) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$001(SimpleMessageListenerContainer.java:97) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$1.invokeListener(SimpleMessageListenerContainer.java:189) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.invokeListener(SimpleMessageListenerContainer.java:1276) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.AbstractMessageListenerContainer.executeListener(AbstractMessageListenerContainer.java:726) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.doReceiveAndExecute(SimpleMessageListenerContainer.java:1219) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.receiveAndExecute(SimpleMessageListenerContainer.java:1189) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer.access$1500(SimpleMessageListenerContainer.java:97) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at org.springframework.amqp.rabbit.listener.SimpleMessageListenerContainer$AsyncMessageProcessingConsumer.run(SimpleMessageListenerContainer.java:1421) [spring-rabbit-1.7.3.RELEASE.jar:na]
    at java.lang.Thread.run(Thread.java:745) [na:1.8.0_121]
Caused by: java.lang.NoSuchMethodException: com.test.RabbitReceiver.handleMessage([B)
    at java.lang.Class.getMethod(Class.java:1786) ~[na:1.8.0_121]
    at org.springframework.util.MethodInvoker.prepare(MethodInvoker.java:174) ~[spring-core-4.3.9.RELEASE.jar:4.3.9.RELEASE]
    at org.springframework.amqp.rabbit.listener.adapter.MessageListenerAdapter.invokeListenerMethod(MessageListenerAdapter.java:386) ~[spring-rabbit-1.7.3.RELEASE.jar:na]
    ... 12 common frames omitted

我做错了什么？

编辑1:我将方法更改为:

@Override
public void handleMessage(byte[] message) {
    System.out.println(message);
}

这有效，但完全无法使用。它只是显示如下:

如何将其映射到我的 pojo FooA

Answer 1

我刚刚让类实现了 Serialized 接口(interface)，并删除了 JsonMessageConverter。 Json 和 Serialized 是冲突的，所以不起作用。