Ném ResourceAccessException và HttpClientErrorException cho máy khách RestTemplate trong Spring

Question

Sử dụng Spring 4.3.1 trên Apache Tomcat 8.5, Chúng tôi đã triển khai một máy chủ REST xử lý các yêu cầu PUT, POST & PUT. Yêu cầu POST được xử lý theo hình thức:

@POST 
@Consumes({MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON}) 
@Transactional 
public Response postMethod(final MyDomain object) { 
    domainHandler.createDomain(object); 
    return Response.status(201).entity(object).build(); 
} 

Trong xử lý yêu cầu POST ở phía máy chủ, các WebApplicationException được ném, mà được xử lý bởi:

@Provider 
public class WebExceptionMapper implements ExceptionMapper<WebApplicationException> { 
    @Override 
    public Response toResponse(WebApplicationException exception) { 
      int httpStatus = exception.getResponse().getStatus(); 
      ErrorMessage em = new WebErrorMessage(exception.getMessage()); 
      return Response.status(httpStatus).entity(em).build(); 
    } 
} 

Về phía khách hàng:

response = rest.exchange(requestURL, method, requestEntity, MyDomain.class); 

ResourceAccessException được ném:

2017-07-25 15:46:41,489 ERROR [com.my.code.web.presentation.ManagementController:63] (http-nio-8080-exec-7#34): Internal exception occured with cause: 
org.springframework.web.client.ResourceAccessException: I/O error on POST request for "http://localhost:8080/": Server returned HTTP response code: 500 for URL: http://localhost:8080/; nested exception is java.io.IOException: Server returned HTTP response code: 500 for URL: http://localhost:8080/ 
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:633) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:580) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.client.RestTemplate.exchange(RestTemplate.java:498) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at com.my.code.web.integration.client.rest.FeedbackRestClient.callForApiCreateFeedback(FeedbackRestClient.java:218) ~[classes/:?] 
    at com.my.code.web.integration.client.rest.FeedbackRestClient.pushFeedbackData(FeedbackRestClient.java:70) ~[classes/:?] 
    at com.my.code.web.presentation.FeedbackController.feedback(FeedbackController.java:91) ~[classes/:?] 
    at sun.reflect.GeneratedMethodAccessor72.invoke(Unknown Source) ~[?:?] 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[?:1.8.0_131] 
    at java.lang.reflect.Method.invoke(Method.java:498) ~[?:1.8.0_131] 
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:221) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:114) ~[spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:963) [spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:897) [spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) [spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) [spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) [servlet-api.jar:?] 
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) [spring-webmvc-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) [servlet-api.jar:?] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.16] 
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) [spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) [spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.16] 
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) [tomcat-websocket.jar:8.5.16] 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [catalina.jar:8.5.16] 
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [catalina.jar:8.5.16] 
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80) [catalina.jar:8.5.16] 
    at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624) [catalina.jar:8.5.16] 
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [catalina.jar:8.5.16] 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [catalina.jar:8.5.16] 
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799) [tomcat-coyote.jar:8.5.16] 
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-coyote.jar:8.5.16] 
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-coyote.jar:8.5.16] 
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455) [tomcat-coyote.jar:8.5.16] 
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-coyote.jar:8.5.16] 
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142) [?:1.8.0_131] 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617) [?:1.8.0_131] 
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-util.jar:8.5.16] 
    at java.lang.Thread.run(Thread.java:748) [?:1.8.0_131] 
Caused by: java.io.IOException: Server returned HTTP response code: 400 for URL: http://localhost:8080/ 
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1876) ~[?:1.8.0_131] 
    at sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1474) ~[?:1.8.0_131] 
    at org.springframework.http.client.SimpleClientHttpResponse.getBody(SimpleClientHttpResponse.java:85) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at com.my.code.web.integration.client.rest.BufferingClientHttpResponseWrapper.getBody(BufferingClientHttpResponseWrapper.java:46) ~[classes/:?] 
    at com.my.code.web.integration.client.rest.LoggingRequestInterceptor.traceResponse(LoggingRequestInterceptor.java:66) ~[classes/:?] 
    at com.my.code.web.integration.client.rest.LoggingRequestInterceptor.intercept(LoggingRequestInterceptor.java:34) ~[classes/:?] 
    at org.springframework.http.client.InterceptingClientHttpRequest$InterceptingRequestExecution.execute(InterceptingClientHttpRequest.java:85) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.http.client.InterceptingClientHttpRequest.executeInternal(InterceptingClientHttpRequest.java:69) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.http.client.AbstractBufferingClientHttpRequest.executeInternal(AbstractBufferingClientHttpRequest.java:48) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.http.client.AbstractClientHttpRequest.execute(AbstractClientHttpRequest.java:53) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:619) ~[spring-web-4.3.1.RELEASE.jar:4.3.1.RELEASE] 
    ... 47 more 

Câu hỏi:

Tại sao ngoại trừ org.springframework.web.client.ResourceAccessException được ném, nhưng không org.springframework.web.client.HttpClientErrorException, những gì đang xảy ra để xử lý các yêu cầu GET khi WebApplicationException xảy ra?

Các ResourceAccessException ngoại lệ không có phương pháp cho phép tôi để đọc các trạng thái HTTP, ví dụ như getRawStatusCode(), getResponseHeaders() vv

Answer 1

Bởi vì nó gói một IOException, không nhìn vào mã phản hồi thực tế.

Nguyên nhân gốc có vẻ là do BufferingClientHttpResponseWrapper đang cố gắng đọc một cơ thể mà không kiểm tra xem có đầu tiên không.