WebObjects/Web Applications/Development/Custom Error Handling

Exception Page
To provide a custom error handler when an exception is thrown, override the method:

public WOResponse handleException (java.lang.Exception anException, WOContext aContext) { }

For example:

public WOResponse handleException(Exception _exception, WOContext _context) { Session session = (Session) _context.session; // do something to notify user of exception, maybe put a message in the session here ... WOResponse response; if (/* you can't handle exception*/) { response = super.handleException(_exception, _context); }   else { response = pageWithName(YourExceptionPage.class.getName, _context).generateResponse; }   return response; }

Session Expired
To provide a custom error handler when an exception is thrown, override the method:

public WOResponse handleSessionRestorationErrorInContext(WOContext _context) {

For example: public WOResponse handleSessionRestorationErrorInContext(WOContext _context) { Session session = (Session) _context.session; // do something to notify user of exception, maybe put a message in the session here ... WOResponse response = pageWithName(YourErrorPage.class.getName, _context).generateResponse; return response; }

Chuck Hill
This message started to appear in WO 5.2 when an exception was raised in a DirectAction, but only in deployed applications. Here is what is happening:

WODisplayExceptionPages true or false to enable or disable the generation of WOExceptionPages for direct action requests. Default is true in development mode and false in deployment mode.

From http://developer.apple.com/documentation/WebObjects/WOAppProperties/AppProperties/chapter_1_section_1.html

If the page being returned throws during appendToResponse and the app is deployed, all that is displayed is a blank page with the words "Your request produced an error".

To avoid this, either add this to the launch agruments: -DWODisplayExceptionPages=true

Or change the main method in your Application class to look like this:

public static void main(String argv[]) { System.setProperty("WODisplayExceptionPages", "true"); WOApplication.main(argv, Application.class); }

This won't work if you put it in the constructor.