Get user defined exception error message to error jsp page from servlet

[shiva kumar g]

Hi,

My requirement is to throw user defined exception from servlet with some error code/message. As i have configured this user defined exception type and error jsp in web.xml as
<error-page> <exception-type>com.MyownException</exception-type> <location>/responses/myownerror.jsp</location> </error-page>
Coming to user defined exception class i have defined as

public class MyownException extends Exception {
	private String errorCode;
	
	private static final long serialVersionUID = 1L;
	public MyownException(String errorCode) {
		this.errorCode = errorCode;
	}
	public String toString(){
		return ("User defined exception"+errorCode);
	}
}

From my servlet if there is any exception i am throwing MyownException("E001") etc but i am not getting the thrown error message in the jsp.
In error page jsp giving it as

<%
if (exception != null) {
	exception.printStackTrace(new PrintWriter(out));
	out.print("==========="+exception.getMessage());
}
%>

From servlet i am thowing exception as

if (xmlString == null || "".equalsIgnoreCase(xmlString.trim())){
			try {
				System.out.println("********************");
				throw new MyownException("E001");
			} catch (MyownException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}	
		}

But when there is an exception the error page is not getting executed and control is going further from the above try catch block and executing the rest code too.
Help me if there is any issue. Also guide me if i am doing anything wrong.

[Harsha Ka]

Hi,

You are throwing your custom exception and also catching it.So the flow is not going to the JSP. Yow will either need to remove the try-catch block or better, just add the exception object in the request scope and forward it to the JSP.

[Bear Bibeault]

The exception flow should not be going to the JSP nor caught in the servlet. Configure an error handler in the deployment descriptor, log the error, then forward to a JSP that displays a message to the user. The user should never see the exception stack trace, just a customer-appropriate message.

[shiva kumar g]

Hi all,


Thanks for your reply.

My issue has been resolved as i am throwing the custom exception from servlet and keeping the same exception in a request scope as

request.setAttribute("javax.servlet.jsp.jspexception", e);
request.getRequestDispatcher("/responses/error.jsp").forward(request, response);

In error jsp page type casting to custom exception and displaying the nice error message on to the error page

try{
	out.print(((CustomException)request.getAttribute("javax.servlet.jsp.jspexception")).getMessage());
}catch(Exception e){
	out.print(default message);
}

Hope i am doing right.
Once again thanks for the reply.

[Prasad Krishnegowda]

No, you are not doing right.. Writing java code in JSP's is very bad, it is been discredited for a decade now. Time to move on to JSTL...