An elegant method to handle exceptions that occur in Apex processes, validations, etc.

The idea here is to create a nice error page (99 in this example), and to redirect the user to that page in case of an exception.
The redirect_url function (see package code below) returns a urls to error page 99.
Page 99 needs a page item named P99_ERROR_MESSAGE (you can change that in the package of course) so you can show the error text to the user.

The code in your Apex processes, validations, etc. would then look something like this: begin if 1/0 <> 0 then -- Force an error null; end if; -- Example [with some pseudo code] how to force a redirect in your code if [error_X_occurs] then begin apex_util.redirect_url( [URL] ); exception when others then null; -- Needed, otherwise an "ORA-20876: Stop APEX Engine" exception is raised because of the redirect; end; end if; exception when others then -- This is an ideal place to do some logging apex_util.redirect_url( ted_p1090.error_redirect_url(p_error_message => 'An internal error has occurred') ); end;
The [error_X_occurs] section is an example of how to redirect to another error page in your code.
Note the exception handling to prevent an "ORA-20876: Stop APEX Engine" exception.

Package

Package
	Name	TED_P1090
	Source	package ted_p1090 is function error_redirect_url ( p_error_message in varchar2 ) return varchar2 ; end ted_p1090;

Package Body

Package Body
	Name	TED_P1090
	Source	package body ted_p1090 is -- Constants c_error_page_id constant number := 99; -- Apex Error Page ID to redirect to function error_redirect_url ( p_error_message in varchar2 ) return varchar2 is v_error_message varchar2(4000) := p_error_message; v_result varchar2(4000); begin -- Clean up error message for redirect v_error_message := replace(v_error_message, 'ORA-20000: ', null); -- clean self-generated exceptions v_error_message := replace(v_error_message, 'ORA-20001: ', null); -- clean self-generated exceptions -- Apex url syntax: f?p=app:page:session:request:debug:clearcache:itemnames:itemvalues:printerfriendly v_result := 'f?p=' || trim(v('APP_ID')) -- app || ':' || trim(c_error_page_id) -- page || ':' || v('APP_SESSION') -- session || ':' -- request (not needed on the error page) || ':' || v('DEBUG') -- debug || ':' -- clearcache (not needed on the error page) || ':' || 'P' ||trim(c_error_page_id)||'_ERROR_MESSAGE' -- itemnames : item on your error page that contains the error message || ':' || utl_url.escape( replace(v_error_message,':','-') ) -- itemvalues : the replace is needed because any ':' characters would mess up the url || ':' -- printerfriendly (not needed on the error page) ; return v_result; end error_redirect_url; end ted_p1090;