Spring AWS SQS - MessageConversionException

Question

我正在尝试解决 SQS 队列的序列化问题，这是一个代码：

@Configuration
public class QueueConfig {

    @Bean
    public QueueMessagingTemplate messagingTemplate(AmazonSQSAsync amazonSqs, ResourceIdResolver resourceIdResolver) {
        ObjectMapper objectMapper = new ObjectMapper();
        objectMapper.findAndRegisterModules();

        DefaultContentTypeResolver resolver = new DefaultContentTypeResolver();
        resolver.setDefaultMimeType(MimeTypeUtils.APPLICATION_JSON);

        MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
        converter.setSerializedPayloadClass(String.class);
        converter.setObjectMapper(objectMapper);
        return new QueueMessagingTemplate(amazonSqs, resourceIdResolver, converter);
    }
}

这个有效（字符串）：

public void publish(String queue, String value) {
    messagingTemplate.convertAndSend(queue, value);
}

这不起作用（对象）：

public void publish(String queue, Something something) {
    messagingTemplate.convertAndSend(queue, something);
}

我收到错误：

org.springframework.messaging.converter.MessageConversionException: Unable to convert payload with type='com.example.Something', contentType='null', converter=[CompositeMessageConverter[converters=[org.springframework.messaging.converter.StringMessageConverter@433f5e00, org.springframework.messaging.converter.MappingJackson2MessageConverter@74e3e86e]]]

我做错了什么？

Answer 1

我怀疑的是这段代码

converter.setSerializedPayloadClass(String.class);

不如尝试这样做

    MappingJackson2MessageConverter converter = new MappingJackson2MessageConverter();
    return new QueueMessagingTemplate(amazonSqs, resourceIdResolver, converter);

这会在将消息发布到队列之前将请求正文转换为 byte[]。