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

Question

I am new to jsp,when I try to invoke a jsp page by some parameters named cId and passWord,I getting this error,The code I have been trying is given below,I have already gone through the same error which have been seen by googling,but still I am getting the same issue. The code is:

<body>
        <%

        String cidMessage = "cID";
        String passEncrypted = "passWord";
        System.out.println("CID ISSSSSSSSSSSS"+cId);
        if ((cId.equals(cidMessage)) && (passWord.equals(passEncrypted))) {
                        System.out.println("Validation Correct"+cId);
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            Date date = new Date();
            String time = sdf.format(date.getTime());
            String xmlOutput = "<smsreport>"
                    + "<date>" + time + "</date>"
                    + "<result>" + "SUCESS" + "</result>"
                    + "<msgid>" + currentTimeMillis() + "</msgid>"
                    + "<msgparts>" + "1" + "</msgparts>"
                    + "</smsreport>";

            try {
                byte[] contents = xmlOutput.getBytes();
                response.setContentType("text/xml");
                response.setContentLength(contents.length);
                response.getOutputStream().write(contents);
                response.getOutputStream().flush();
            } catch (Exception e) {
                throw new ServletException(e);
            }
        } else {
                           System.out.println("Validation Wrong"+cId);
            SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
            Date date = new Date();
            String time = sdf.format(date.getTime());
            String xmlOutput = "<smsreport>"
                    + "<date>" + time + "</date>"
                    + "<result>ERROR</result>"
                    + "<msgid>" + "ErrorCode" + "</msgid>"
                    + "<msgparts>" + "ErrorMessage" + "</msgparts>"
                    + "</smsreport>";

            try {
                byte[] contents = xmlOutput.getBytes();
                response.setContentType("text/xml");
                response.setContentLength(contents.length);
                response.getOutputStream().write(contents);
                response.getOutputStream().flush();
            } catch (Exception e) {
                throw new ServletException(e);
            }

        }
    %>
</body>

Santosh Santosh · Accepted Answer · 2013-02-19T06:58:51

If you check the documentation of getOutputStream() method: It mentions

Throws:IllegalStateException - if the getWriter method has been called on this response .

This means that you can call either getWriter() or getOutputStream() methods.
Now in JSP (and eventually in compiled servlet), there is an implicit variable defined called out . This is nothing but an instance of PrintWriter class. This means that on the response object, getWriter() is already called and hence on calling getOutputStream() you get IllegalStateException
Now as solution for this problem, as some people have pointed out, move this code into a servlet where you have full control and use the outputstream the way you want.

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

3 Answers