springMVC中使用HttpServletResponse?

Question

在AOP中，需要使用腾讯提供的jar包，但是在这个SDK中需要调用HttpServletResponse的getWriter方法来返回异常信息，这就导致和springMVC本身的调用冲突：

[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; n
ested exception is java.lang.IllegalStateException: getWriter() has already been called for this response] with root cause

java.lang.IllegalStateException: getWriter() has already been called for this response
        at org.apache.catalina.connector.Response.getOutputStream(Response.java:591) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.connector.ResponseFacade.getOutputStream(ResponseFacade.java:194) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.http.server.ServletServerHttpResponse.getBody(ServletServerHttpResponse.java:89) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.writeInternal(AbstractJackson2HttpMessageConverter.java:251) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.http.converter.AbstractGenericHttpMessageConverter.write(AbstractGenericHttpMessageConverter.java:106) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodProcessor.writeWithMessageConverters(AbstractMessageConverterMethodProcessor.java:231) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3
.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.handleReturnValue(RequestResponseBodyMethodProcessor.java:174) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.method.support.HandlerMethodReturnValueHandlerComposite.handleReturnValue(HandlerMethodReturnValueHandlerComposite.java:81) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:113) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:827) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:738) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:85) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:967) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:901) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:970) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:861) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:635) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:846) ~[spring-webmvc-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at javax.servlet.http.HttpServlet.service(HttpServlet.java:742) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52) ~[tomcat-embed-websocket-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:99) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.web.filter.HttpPutFormContentFilter.doFilterInternal(HttpPutFormContentFilter.java:108) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.web.filter.HiddenHttpMethodFilter.doFilterInternal(HiddenHttpMethodFilter.java:81) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:197) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:107) ~[spring-web-4.3.13.RELEASE.jar:4.3.13.RELEASE]
        at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:199) ~[tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:81) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:803) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1459) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) [na:1.8.0_144]
        at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) [na:1.8.0_144]
        at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) [tomcat-embed-core-8.5.23.jar:8.5.23]
        at java.lang.Thread.run(Thread.java:748) [na:1.8.0_144]

代码如下：

            HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest();
            HttpServletResponse response = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getResponse();
            LoginService service = new LoginService(request,response);
            service.check();
       

反编译的jar包代码

            this.response.setContentType("application/json");
            this.response.setCharacterEncoding("utf-8");
            this.response.getWriter().print(json.toString());

该如何避免这种冲突？

Answer 1

创建对象是用 包名.类名 去创建对象.这不就能区分是哪个对象调用的哪个方法.