Re: xeres gives Unexpected runtime & NullPointer exceptions under load for multi threaded application

Hi,

Xerces DOM implementation is not thread safe [1] even if you're only doing 
read operations. You must synchronize your access to the DOM. If you don't 
synchronize you may get NPEs (in seemingly random places) or other errors 
in a multi-threaded application.

Thanks.

[1] http://xerces.apache.org/xerces2-j/faq-dom.html#faq-1

Michael Glavassevich
XML Technologies and WAS Development
IBM Toronto Lab
E-mail: [email protected]
E-mail: [email protected]

nk2013 <[email protected]> wrote on 20/01/2013 01:06:08 AM:

> Exception occurs when simple load of messages (approx. 5000 messages of 
4 -
> 5KB) posted
> 
> XML Messages posted to IBM MQ Queue with MQ API - 
> 
> Unexpected runtime exception; nested exception is: 
>    java.lang.NullPointerException
> 
> Please find complete stacktrace below - 
> 
> Unexpected runtime exception; nested exception is: t
>    java.lang.NullPointerException
> java.lang.NullPointerException
>    at org.apache.xerces.dom.ParentNode.internalInsertBefore(Unknown 
Source)
>    at org.apache.xerces.dom.ParentNode.insertBefore(Unknown Source)
>    at org.apache.xerces.dom.NodeImpl.appendChild(Unknown Source)
> ** Pls note it happens under load only > 4K
> ** Using xercesImpl.jar
> 
> Need resolution on top priority, issue in production. 
> Any help is appreciated.
> 
> 
> 
> 
> 
> 
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