exception - Grails error handler always receives null pointer -

we have custom error controller gets called after of our errors. however, of our errors thrown end coming controller null pointers, though original error not null pointer. ideas? code below. bootstrap , urlmappings available if needed. thanks

error handler method

def handleerrors = {      def exception = request.exception.cause.class        if (exception)      {          exception ex = request.exception  //this exception npe             ... 

block of code throwing exception. did not have try catch in here, wanted add sure exception being thrown not npe. file not found exception.

try{         def writer = new filewriter( new file(filesavelocation));     }      catch ( ex)     {         throw(ex)     } 

edit: adding exception pushed exception handler

exception:org.codehaus.groovy.grails.web.errors.grailswrappedruntimeexception cause:org.springframework.web.util.nestedservletexception: request processing failed; nested exception java.lang.nullpointerexception 

it's not because you're referencing null inside error handler, , inadvertently throwing exception, again caught?

can try changing:

def exception = request.exception.cause.class   

to

def exception = request?.exception?.cause?.class