告诉Jackson2JsonMessageConverter在Amqp.inboundAdapter中使用我自己的类

问题描述

鉴于我有IntegrationFlow和AMQP队列的入站适配器：

@Bean
public IntegrationFlow readMessagesFlow(
        ConnectionFactory rabbitConnectionFactory,ObjectMapper jacksonObjectMapper) {
    return IntegrationFlows.from(
            Amqp.inboundAdapter(rabbitConnectionFactory,QUEUE)
                    .messageConverter(new Jackson2JsonMessageConverter(jacksonObjectMapper))
    )
            .log(INFO,AMQP_LOGGER_CATEGORY)
            .get();
}

当某个外部系统使用JSON正文发送消息时，我发现它们使用__TypeId__=THEIR_INTERNAL_CLASS。

我想将JSON主体映射到自己的类。

当前，由于ClassCastException不可用，它在THEIR_INTERNAL_CLASS上失败。

如何告诉Jackson2JsonMessageConverter使用自己的课程？

解决方法

请参阅此转换器方法：

/**
 * Set the precedence for evaluating type information in message properties.
 * When using {@code @RabbitListener} at the method level,the framework attempts
 * to determine the target type for payload conversion from the method signature.
 * If so,this type is provided in the
 * {@link MessageProperties#getInferredArgumentType() inferredArgumentType}
 * message property.
 * <p> By default,if the type is concrete (not abstract,not an interface),this will
 * be used ahead of type information provided in the {@code __TypeId__} and
 * associated headers provided by the sender.
 * <p> If you wish to force the use of the  {@code __TypeId__} and associated headers
 * (such as when the actual type is a subclass of the method argument type),* set the precedence to {@link Jackson2JavaTypeMapper.TypePrecedence#TYPE_ID}.
 * @param typePrecedence the precedence.
 * @see DefaultJackson2JavaTypeMapper#setTypePrecedence(Jackson2JavaTypeMapper.TypePrecedence)
 */
public void setTypePrecedence(Jackson2JavaTypeMapper.TypePrecedence typePrecedence) {

这是此事的文档：https://docs.spring.io/spring-amqp/docs/2.2.11.RELEASE/reference/html/#json-message-converter

,

这是一种方法：

Jackson2JsonMessageConverter messageConverter = new Jackson2JsonMessageConverter(jacksonObjectMapper);
DefaultClassMapper defaultClassMapper = new DefaultClassMapper();
defaultClassMapper.setDefaultType(MyOwnClass.class);
messageConverter.setClassMapper(defaultClassMapper);

并在messageConverter中使用Amqp.inboundAdapter