我正在使用SpringXD,其中我的Rabbit源具有outputType application / json。下一个模块将其接收并将其转换为Java Object。 RabbitMq是我的运输巴士。
我的配置非常标准,例如:
@EnableIntegration
@ImportResource("classpath:some.xml")
@ComponentScan(basePackages = "com.something")
public class MyConfigClass {
@Autowired
private Jackson2JsonObjectMapper jackson2JsonObjectMapper;
@Bean
public MessageChannel input() {
return new DirectChannel();
}
@Bean
public MessageChannel inputObject() {
return new DirectChannel();
}
@Bean
public MessageChannel output() {
return new DirectChannel();
}
@Bean
public MessageChannel outputObject() {
return new DirectChannel();
}
@Bean
public Jackson2JsonObjectMapper objectMapper() {
ObjectMapper mapper = new ObjectMapper();
mapper.registerModule(new JodaModule());
mapper.setSerializationInclusion(JsonInclude.Include.NON_NULL);
return new Jackson2JsonObjectMapper(mapper);
}
@Bean
@Transformer(inputChannel = "input", outputChannel = "inputObject")
public JsonToObjectTransformer jsonToObjectTransformer() {
return new JsonToObjectTransformer(someTargetClass.class, jackson2JsonObjectMapper);
}
@Bean
@Transformer(inputChannel = "outputObject", outputChannel = "output")
public ObjectToJsonTransformer objectToJsonTransformer() {
return new ObjectToJsonTransformer(jackson2JsonObjectMapper);
}
}
然后在另一堂课中,我有这样的东西:
public class AnotherClass {
@Transformer(inputChannel = "inputObject", outputChannel = "outputObject")
public Message<someTargetClass> transform(Message<someTargetClass> incoming) {
//Here I'm getting Caused by: org.springframework.messaging.MessageHandlingException: nested exception is java.lang.ClassCastException: java.lang.String cannot be cast to com.whatever.someTargetClass
SomeTargetClass messagePayload = incoming.getPayload();
}
}
因此流程为输入-> inputObject-outputObject->输出
但是以某种方式,我得到一个classCastException作为输入有效载荷,它作为字符串而不是作为Java对象(someTargetClass类型)。
Caused by: org.springframework.messaging.MessageHandlingException: nested exception is java.lang.ClassCastException: java.lang.String cannot be cast to com.whatever.someTargetClass at org.springframework.integration.handler.MethodInvokingMessageProcessor.processMessage(MethodInvokingMessageProcessor.java:96) ~[spring-integration-core-4.2.5.RELEASE.jar:na] at org.springframework.integration.transformer.AbstractMessageProcessingTransformer.transform(AbstractMessageProcessingTransformer.java:90) ~[spring-integration-core-4.2.5.RELEASE.jar:na] at org.springframework.integration.transformer.MessageTransformingHandler.handleRequestMessage(MessageTransformingHandler.java:89) ~[spring-integration-core-4.2.5.RELEASE.jar:na] ... 52 common frames omitted
因此,某种程度上看来,通过渠道的流量无法正常工作。我想念什么?
我的理论是,源正在生成一个字符串,事实是json没有被传输,当转换器接收到该字符串时无法将其转换为SomeTargetClass。如果是这样,则应解决此问题:
在变换方法中更改:
SomeTargetClass messagePayload = incoming.getPayload();
至:
String jsonString = incoming.getPayload();
SomeTargetClass messagePayload = (SomeTargetClass) JSON.std.beanFrom(SomeTargetClass.class, jsonString);
这是使用杰克逊(Jackson Jr),但我确定您可以在杰克逊(Jackson)中找到替代者。