java.lang.IllegalStateException: Cannot call sendRedirect() after the response has been committed

[Farakh khan]

Hello,

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

if(referer==null || referer.equals("")){
	res.sendRedirect("/servlet/Index");
}
else{		
	res.sendRedirect(referer);		
}

Tomcat Log:

java.lang.IllegalStateException: Cannot call sendRedirect() after the response has been committed
at org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:483)
at LoginDAO.login(LoginDAO.java:108)
at LoginManager.doPost(LoginManager.java:185)

Please advise

Best regards

[William Brogden]

That is really pretty clear.

Somewhere in your code, enough output is written to the response stream to cause the output buffer to be flushed, sending the response headers - this constitutes commitment of the response since those headers can not be recalled.

So - your task is to figure out where that output gets written.

Bill

[Paul Clapham]

Your basic strategy for fixing that error should be to refactor your code. The basic overview of the servlet should be like this:

1. Decide whether it's necessary to redirect.

2. Redirect if it is necessary.

3. Otherwise, continue doing the servlet's actual work, including writing data to the response.

[Farakh khan]

Hello,

Thanks all from the bottom of my heart for providing accurate clues. I changed my following servlet part from this code:

res.setContentType("text/html");
	PrintWriter out=res.getWriter();

To this code:

res.setContentType("text/html; charset=UTF-8");
StringWriter sWriter = new StringWriter();  
PrintWriter out = new PrintWriter(sWriter);  

res.getWriter().print(sWriter.toString());

and problem fixed

Best regards