java - Errai-jaxrs - 错误请求

Question

我在使用我的应用程序运行 Errai-jaxrs 时遇到了很大的问题，我从 GWT 开发模式中收到此错误:

org.jboss.errai.enterprise.client.jaxrs.api.ResponseException: Bad Request    
at org.jboss.errai.enterprise.client.jaxrs.AbstractJaxrsProxy$1.onResponseReceived(AbstractJaxrsProxy.java:132)    
at com.google.gwt.http.client.Request.fireOnResponseReceived(Request.java:287)    
at com.google.gwt.http.client.RequestBuilder$1.onReadyStateChange(RequestBuilder.java:395)    
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)    
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)    
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    
at java.lang.reflect.Method.invoke(Method.java:474)    
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)    
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)    
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)    
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessagesWhileWaitingForReturn(BrowserChannelServer.java:337)    
at com.google.gwt.dev.shell.BrowserChannelServer.invokeJavascript(BrowserChannelServer.java:218)    
at com.google.gwt.dev.shell.ModuleSpaceOOPHM.doInvoke(ModuleSpaceOOPHM.java:136)    
at com.google.gwt.dev.shell.ModuleSpace.invokeNative(ModuleSpace.java:561)    
at com.google.gwt.dev.shell.ModuleSpace.invokeNativeObject(ModuleSpace.java:269)    
at com.google.gwt.dev.shell.JavaScriptHost.invokeNativeObject(JavaScriptHost.java:91)    
at com.google.gwt.core.client.impl.Impl.apply(Impl.java)    
at com.google.gwt.core.client.impl.Impl.entry0(Impl.java:213)    
at sun.reflect.GeneratedMethodAccessor56.invoke(Unknown Source)    
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)    
at java.lang.reflect.Method.invoke(Method.java:474)    
at com.google.gwt.dev.shell.MethodAdaptor.invoke(MethodAdaptor.java:103)    
at com.google.gwt.dev.shell.MethodDispatch.invoke(MethodDispatch.java:71)    
at com.google.gwt.dev.shell.OophmSessionHandler.invoke(OophmSessionHandler.java:172)    
at com.google.gwt.dev.shell.BrowserChannelServer.reactToMessages(BrowserChannelServer.java:292)    
at com.google.gwt.dev.shell.BrowserChannelServer.processConnection(BrowserChannelServer.java:546)    
at com.google.gwt.dev.shell.BrowserChannelServer.run(BrowserChannelServer.java:363)    
at java.lang.Thread.run(Thread.java:722)

在服务器端:

[INFO] Caused by: org.codehaus.jackson.map.exc.UnrecognizedPropertyException: Unrecognized field "^EncodedType" (Class com.mycompany.client.shared.Customer), not marked as ignorable
[INFO]  at [Source: org.mortbay.jetty.HttpParser$Input@115194d; line: 1, column: 18] (through reference chain: com.mycompany.client.shared.Customer["^EncodedType"])
[INFO]  at org.codehaus.jackson.map.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:53)
[INFO]  at org.codehaus.jackson.map.deser.StdDeserializationContext.unknownFieldException(StdDeserializationContext.java:267)
[INFO]  at org.codehaus.jackson.map.deser.std.StdDeserializer.reportUnknownProperty(StdDeserializer.java:673)
[INFO]  at org.codehaus.jackson.map.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:659)
[INFO]  at org.codehaus.jackson.map.deser.BeanDeserializer.handleUnknownProperty(BeanDeserializer.java:1365)
[INFO]  at org.codehaus.jackson.map.deser.BeanDeserializer._handleUnknown(BeanDeserializer.java:725)
[INFO]  at org.codehaus.jackson.map.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:703)
[INFO]  at org.codehaus.jackson.map.deser.BeanDeserializer.deserialize(BeanDeserializer.java:580)
[INFO]  at org.codehaus.jackson.map.ObjectMapper._readValue(ObjectMapper.java:2704)

从堆栈跟踪来看，它看起来像是一个错误的请求。这个后端是 RestEasy + Guice，它配置得非常正确，因为在我尝试使用 errai-jaxrs 之前，我只是使用普通的 GWT RequestBuilder，它工作得很好。我不确定问题出在哪里，但这是我的代码:

CustomerService.java

@Path("/customerservice")
public interface CustomerService {
    @GET
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)     
    public Customer getCustomer(String id);

    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.TEXT_PLAIN)
    public String createCustomer(Customer Customer);
}

CustomerServiceImpl.java

@Singleton
public class CustomerServiceImpl implements CustomerService {
    @Override
    public Customer getCustomer(String id) {
        return new Customer();
    }

    @Override
    public String createCustomer(Customer Customer) {
        return "1";
    }
}

在客户端:

@Inject
private Caller<CustomerService> customerService;

@EventHandler("submit")
public void createCustomer(ClickEvent event) {   
    event.preventDefault();
    Customer customer = new Customer();
    customerService.call(new RemoteCallback<String>() {
        @Override
        public void callback(String response) {
            Window.alert("Customer created: " + response);
        }
    }).createCustomer(customer);
}

可能是什么问题？

Answer 1

我可以从堆栈跟踪中看到，您正在使用 Jackson 在服务器端编码请求和响应数据，但客户端使用 Errai 的默认编码格式。

您必须决定是使用 Errai 的编码格式还是 Jackson。

Errai 编码

Errai 编码格式的优点是它包含更多在线类型信息(例如您看到 Jackson 解析器提示的“^EncodedType”属性)。当您的 JAX-RS API 主要由 Errai 客户端使用时，这是最佳选择。这也是您能够通过线路发送此类对象的唯一方式:

@Portable class TypeWithPolymorphicField {
  private Object foo = new Foo();
}

要在服务器端启用 Errai 编码(而不是 Jackson)，您需要使用您的应用部署 errai-jaxrs-provider-[version].jar。来自 Errai Reference Guide :

<dependency>
  <groupId>org.jboss.errai</groupId>
  <artifactId>errai-jaxrs-provider</artifactId>
  <version>${errai.version}</version>
</dependency>

jackson 编码

另一方面，如果您的 JAX-RS API 供非 Errai 客户端使用，他们可能会发现 Jackson 编码更加愉快和熟悉。如果您选择这样做，则需要告诉客户端使用 Jackson 编码而不是默认值。来自 Errai Reference guide :

The following options are available for activating Jackson marshalling on the client. Note that this is a client-side configuration, the JAX-RS endpoint is assumed to already return a Jackson representation (Jackson is supported by all JAX-RS implementations). The errai-jaxrs-provider.jar does not have to be deployed on the server in this case!

<script type="text/javascript">
  erraiJaxRsJacksonMarshallingActive = true;
</script>

or by using a JSNI method:

private native void setJacksonMarshallingActive(boolean active) /*-{  
  $wnd.erraiJaxRsJacksonMarshallingActive = active;
}-*/;

or by simply invoking:

RestClient.setJacksonMarshallingActive(true);

最后注意:不要同时执行上述两项操作，否则您将遇到相反的问题!您必须将客户端或服务器配置为远离其自然默认值。