clarification regarding RequestDispatcher usage

[Prakash Moorthy]

Hi

am calling a jsp(chk.jsp) from a html file(branch.html) by the html form action, then in chk.jsp forwarding the requset to the branch.html page by using requestDispatcher

RequestDispatcher view = request.getRequestDispatcher("branch.html");
view.forward(request, response);

am getting the following error,

org.apache.jasper.JasperException: java.lang.IllegalStateException: getOutputStream() has already been called for this response
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:534)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:421)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)

root cause

java.lang.IllegalStateException: getOutputStream() has already been called for this response
org.apache.catalina.connector.Response.getWriter(Response.java:608)
org.apache.catalina.connector.ResponseFacade.getWriter(ResponseFacade.java:200)
org.apache.jasper.runtime.JspWriterImpl.initOut(JspWriterImpl.java:125)
org.apache.jasper.runtime.JspWriterImpl.flushBuffer(JspWriterImpl.java:118)
org.apache.jasper.runtime.PageContextImpl.release(PageContextImpl.java:189)
org.apache.jasper.runtime.JspFactoryImpl.internalReleasePageContext(JspFactoryImpl.java:122)
org.apache.jasper.runtime.JspFactoryImpl.releasePageContext(JspFactoryImpl.java:79)
org.apache.jsp.chk_jsp._jspService(chk_jsp.java:115)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:73)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:378)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:320)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:265)
javax.servlet.http.HttpServlet.service(HttpServlet.java:722)

but if i use the <jsp:forward page="branch.html" />, then its working fine, and it's also working fine, if i use the branch.html as branch.jsp

please clarify.

Thanks.

[Tarun Bolla]

https://coderanch.com/t/289883/JSP/java/IllegalStateException-getOutputStream-has-already-been

[Ashwin Sridhar]

please post your jsp code for more clarity

[Prakash Moorthy]

Hi Ashwin

the jsp code

<%@ page import="com.work.bean.Branch, java.io.*, java.util.*" %>

<%!
ArrayList<Branch> bList = new ArrayList<Branch>();
%>

<%

String prevAction = (String)session.getAttribute("prevAction");

if(prevAction == null || !prevAction.equals("add"))
bList.clear();

String action=request.getParameter("saction");

session.setAttribute("prevAction",action);

Branch br = new Branch();
br.setName(request.getParameter("bname"));
System.out.println("bname ="+request.getParameter("bname")+"\n");
bList.add(br);

session.setAttribute("bList",bList);

if(action.equals("add")){
RequestDispatcher view = request.getRequestDispatcher("branch.html");
view.forward(request, response);
}
%>

[Bear Bibeault]

That code should be in a servlet, not a JSP.

Java code in a JSP has been considered a poor practice and discredited for almost 10 years noes because of issues such as this (among many other good reasons).

Your first step is to refactor your application to use servlets and JSPs appropriately. You may find this article helpful.

And, please UseCodeTags when posting code to the forums.