我正在获取java.lang.IllegalStateException：此响应已调用getOutputStream（）异常

Question

java.lang.IllegalStateException: getOutputStream() has already been called for this response

Hi I'm getting above exception while m trying to open a pdf file through my java code

Here is my Java code. I am using IText to create pdf

@RequestMapping(value = "/pdf", method = RequestMethod.POST)
public String pdf(ActivitiesForm activitiesForm, Model model,
        HttpSession session,HttpServletResponse response) throws InstanceNotFoundException, IOException,
        DocumentException {

    String PATH = "/home/space/workspace/trainning/Trainning/Performance.pdf";
    // step 1
    Document document = new Document();
    // step 2
     FileOutputStream fos = new FileOutputStream(PATH);
    PdfWriter.getInstance(document,fos);
    // step 3
    document.open();
    // step 4
    PdfPTable table;

    table = new PdfPTable(3);
    table.setWidthPercentage(100);
    PdfPCell cell;

    cell = new PdfPCell(new Phrase("Roll No"));
    cell.setColspan(1);
    // cell.setBorder(Rectangle.NO_BORDER);
    table.addCell(cell);
    cell = new PdfPCell(new Phrase("Name"));
    cell.setColspan(1);
    // cell.setBorder(Rectangle.NO_BORDER);
    table.addCell(cell);
    cell = new PdfPCell(new Phrase("Performance"));
    cell.setColspan(1);
    // cell.setBorder(Rectangle.NO_BORDER);
    table.addCell(cell);

    Integer count = rollService.getRollCount();
    Integer countpts = creditptsService.getPtsCount();

    if (countpts != null) {
        for (Integer i = 1; i <= count; i++) {
            Roll roll = rollService.getRollNoById(Long.parseLong(i
                    .toString()));

            List<Creditpts> creditpts = creditptsService.getRollById(roll
                    .getId());

            Integer performance = 0;

            if (creditpts == null) {

                cell = new PdfPCell(new Phrase("" + roll.getRollno()));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

                cell = new PdfPCell(new Phrase("" + roll.getStudentName()));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

                cell = new PdfPCell(new Phrase("0"));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

            } else {
                Iterator<Creditpts> creIterator = creditpts.iterator();

                while (creIterator.hasNext()) {
                    Creditpts creditpt = creIterator.next();

                    performance += creditpt.getCrdpts();
                }

                cell = new PdfPCell(new Phrase("" + roll.getRollno()));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

                cell = new PdfPCell(new Phrase("" + roll.getStudentName()));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

                cell = new PdfPCell(new Phrase("" + performance));
                cell.setColspan(1);
                // cell.setBorder(Rectangle.NO_BORDER);
                table.addCell(cell);

            }
        }
    }
    document.add(table);
    document.close();

    fos.close();
    FileInputStream baos = new FileInputStream(PATH);

    // set some response headers
    response.setHeader("Expires", "0");
    response.setHeader("Cache-Control", "must-revalidate, post-check=0, pre-check=0");
    response.setHeader("Pragma", "public");
    response.setContentType("application/pdf");

    response.setContentLength((int) new File(PATH).length());
    OutputStream os = response.getOutputStream();
    byte buffer[] = new byte[8192];
    int bytesRead, i;

    while ((bytesRead = baos.read(buffer)) != -1) {
        os.write(buffer, 0, bytesRead);
    }
    os.flush();
    os.close();
}

I have paste my pdf creation and opening code what i'm doing wrong here mi missing some thing...

Here is full stack trace:

java.lang.IllegalStateException: getOutputStream() has already been called for this response
at org.apache.catalina.connector.Response.getWriter(Response.java:633)
at org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:214)
at javax.servlet.ServletResponseWrapper.getWriter(ServletResponseWrapper.java:105)
at org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:125)
at org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:118)
at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:336)
at org.apache.jasper.runtime.JspWriterImpl.write(JspWriterImpl.java:353)
at org.apache.jsp.jsp.activity_jsp._jspService(activity_jsp.java:402)
at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:432)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:390)
at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:334)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684)
at org.apache.catalina.core.ApplicationDispatcher.doInclude(ApplicationDispatcher.java:593)
at org.apache.catalina.core.ApplicationDispatcher.include(ApplicationDispatcher.java:530)
at org.springframework.web.servlet.view.InternalResourceView.renderMergedOutputModel(InternalResourceView.java:229)
at org.springframework.web.servlet.view.AbstractView.render(AbstractView.java:262)
at org.springframework.web.servlet.DispatcherServlet.render(DispatcherServlet.java:1265)
at org.springframework.web.servlet.DispatcherServlet.processDispatchResult(DispatcherServlet.java:1016)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:965)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:859)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:883)
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:792)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:641)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:928)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:987)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:539)
at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:298)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1110)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:603)
at java.lang.Thread.run(Thread.java:722)

Answer 1

Add the following inside the end of the try/catch to avoid the error that appears when the JSP engine flushes the response via getWriter()

out.clear(); // where out is a JspWriter
out = pageContext.pushBody();

This isn't best practice, but it avoids the errors in your logs. Ideally we should do this in Servlet and not in JSP. If you still needs it in JSP, follow above code to get rid off the error.

Answer 2

You handle the request completely in java code, and then the Spring/container's functionality kicks in trying to handle the same request by rendering some jsp. You need to disable this functionality in this particular case.

Answer 3

As you can see in the stack trace, the JSP calls response.getWriter(), but the exception message says there was a call to response.getOutputStream() before. You cannot call both methods on the same response object.

check below links:

https://stackoverflow.com/a/3540474/2333119

and

https://stackoverflow.com/a/14951581/2333119