java.lang.IllegalStateException: getWriter() уже вызван для этого ответа

Question

Привет Я пытаюсь загрузить файл с моей веб-службы, я получаю файл от службы, однако я получаю исключение на линии, где я получение сценария ответа сервлета и не знаю, что вызывает проблему.

private void downloadFile(HttpServletRequest request, HttpServletResponse response) { 
     ServletOutputStream servletStream; 
     try { 
      if (fileImpl == null) { 
       fileImpl = new FileHandlerImplService(); 
      } 
      if (service == null) { 
       service = fileImpl.getFileHandlerImplPort(new MTOMFeature()); 
      } 
      String fileName = request.getParameter("fileName"); 
      byte[] data = service.downloadFile(fileName, 
        request.getSession().getAttribute("user").toString().trim()); 
      File file = new File(fileName); 
      OutputStream outStream = new FileOutputStream(file); 
      BufferedOutputStream bufferStream = new BufferedOutputStream(outStream); 
      bufferStream.write(data); 
      bufferStream.close(); 

      String mimeType = getServletContext().getMimeType(file.getAbsolutePath()); 
      response.setContentType(mimeType != null ? mimeType : "application/octet-stream"); 
      response.setContentLength((int) file.length()); 
      response.setHeader("Content-Disposition", "attachment; filename=\"" + fileName + "\""); 
      InputStream inputStream = new FileInputStream(file); 
      servletStream = response.getOutputStream(); 
      byte[] bufferData = new byte[1024*1024]; 
      int read = 0; 
      while ((read = inputStream.read(bufferData)) != -1) { 
       servletStream.write(bufferData, 0, read); 
      } 
      servletStream.flush(); 
      servletStream.close(); 
      inputStream.close(); 
      file.deleteOnExit(); 
      response.sendRedirect("downloadFile.jsp"); 
     } catch (Exception e) { 
      e.printStackTrace(); 
     } 
    } 

Вот исключение я получаю

severe: java.lang.IllegalStateException: getWriter() has already been called for this response 
    at org.apache.catalina.connector.Response.getOutputStream(Response.java:746) 
    at org.apache.catalina.connector.ResponseFacade.getOutputStream(ResponseFacade.java:206) 
    at servlets.FileRequestHandler.downloadFile(FileRequestHandler.java:90) 
    at servlets.FileRequestHandler.processRequest(FileRequestHandler.java:58) 
    at servlets.FileRequestHandler.doPost(FileRequestHandler.java:200) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:707) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) 
    at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) 
    at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) 
    at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) 
    at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) 
    at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260) 
    at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188) 
    at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191) 
    at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168) 
    at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189) 
    at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136) 
    at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114) 
    at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) 
    at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838) 
    at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55) 
    at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564) 
    at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544) 
    at java.lang.Thread.run(Thread.java:744) 
Info: visiting unvisited references 
Info: visiting unvisited references 
Info: visiting unvisited references 
Info: Loading application [JigarJoshiWebClient] at [/JigarJoshiWebClient] 
Info: JigarJoshiWebClient was successfully deployed in 481 milliseconds. 

Answer 1

Вы должны действительно переместить логику данных от сервлета возможно DataAccessLayer.

http://tomcat.apache.org/tomcat-5.5-doc/servletapi/javax/servlet/ServletResponse.html

Answer 2

Причина я думаю, что вы получаете IllegalStateException потому, что вы звоните response.sendRedirect() после совершения выходной т.е. после выполнения заподлицо().

Вы можете удалить строку response.sendRedirect() и попробовать запустить приложение. Он должен работать!