Java REST API:无法反序列化START\u数组令牌之外的对象实例

我有一个使用Java和Jersey编写的RESTAPI。下面是WEB API的相关代码

 @GET
    @Path("/getAllPhase1")
    @Produces(MediaType.APPLICATION_JSON)  
    public List<Phase1Bean> getAllPhase1()
    {
        Phase1Interface phase1Interface = new Phase1Impl();
        List<Phase1Bean> allPhase1 = phase1Interface.getAllPhase1();
        return allPhase1;
    }

不幸的是，这会产生以下错误

Exception in thread "main" javax.ws.rs.client.ResponseProcessingException: com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of bean.Phase1Bean out of START_ARRAY token
 at [Source: org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$UnCloseableInputStream@2fb3536e; line: 1, column: 1]
    at org.glassfish.jersey.client.JerseyInvocation.translate(JerseyInvocation.java:806)
    at org.glassfish.jersey.client.JerseyInvocation.access$700(JerseyInvocation.java:92)
    at org.glassfish.jersey.client.JerseyInvocation$2.call(JerseyInvocation.java:700)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:315)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:297)
    at org.glassfish.jersey.internal.Errors.process(Errors.java:228)
    at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:444)
    at org.glassfish.jersey.client.JerseyInvocation.invoke(JerseyInvocation.java:696)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.method(JerseyInvocation.java:420)
    at org.glassfish.jersey.client.JerseyInvocation$Builder.get(JerseyInvocation.java:316)
    at JerseyClientGet.main(JerseyClientGet.java:32)
Caused by: com.fasterxml.jackson.databind.JsonMappingException: Can not deserialize instance of bean.Phase1Bean out of START_ARRAY token
 at [Source: org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$UnCloseableInputStream@2fb3536e; line: 1, column: 1]
    at com.fasterxml.jackson.databind.JsonMappingException.from(JsonMappingException.java:164)
    at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:691)
    at com.fasterxml.jackson.databind.DeserializationContext.mappingException(DeserializationContext.java:685)
    at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromArray(BeanDeserializerBase.java:1215)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:151)
    at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:126)
    at com.fasterxml.jackson.databind.ObjectReader._bind(ObjectReader.java:1233)
    at com.fasterxml.jackson.databind.ObjectReader.readValue(ObjectReader.java:677)
    at com.fasterxml.jackson.jaxrs.base.ProviderBase.readFrom(ProviderBase.java:777)
    at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.invokeReadFrom(ReaderInterceptorExecutor.java:256)
    at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:235)
    at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:155)
    at org.glassfish.jersey.message.internal.MessageBodyFactory.readFrom(MessageBodyFactory.java:1085)
    at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:874)
    at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:808)
    at org.glassfish.jersey.client.ClientResponse.readEntity(ClientResponse.java:326)
    at org.glassfish.jersey.client.JerseyInvocation.translate(JerseyInvocation.java:803)
    ... 10 more
Java Result: 1

---

如何解决此问题？

GET方法返回的是一个列表，而不是一个Phase1Bean对象-因此错误消息中提到了“START\u ARRAY”标记。您可以更改客户端

.get（）

方法以接收列表，然后从中提取Phase1Bean项

client.target("http://localhost:8080/xxx/rest")
        .path("phase1/getAllPhase1")
        .request(MediaType.APPLICATION_JSON)
        .get(new GenericType<List<Phase1Bean>>(){});

client.target（“http://localhost:8080/xxx/rest")
.路径（“阶段1/getAllPhase1”）
.request（MediaType.APPLICATION_JSON）
.get（新的GenericType（）{}）；

---

另一种方法是将列表包装到另一个对象（例如Phase1BeanResponse）中，该对象包含列表以及可能与项目相关的其他元数据。

您应该使用

get（new-GenericType（）{}）。您所做的将为您提供一个原始列表，其中将填充LinkedHashMaps，而不是Phase1Bean
client.target("http://localhost:8080/xxx/rest")
        .path("phase1/getAllPhase1")
        .request(MediaType.APPLICATION_JSON)
        .get(new GenericType<List<Phase1Bean>>(){});