Subj : Re: NullPointerException
To   : Arumugam Appadurai <aappadurai@apptera.com>
From : Igor Bukanov <igor@fastmail.fm>
Date : Wed May 28 2003 03:38 pm

Arumugam Appadurai wrote:
> I am using Jdk1.4.1
> The following is the one that I am doing exactly, 
> 
>     private Context mCtx = null;
>     private Scriptable mScope = null;    
>     ResourceWriter resWr = null;
> 
>         mCtx = Context.enter();
>         resWr = new ResourceWriter(new PrintWriter(System.out));
>         mScope = mCtx.initStandardObjects(null);
>         Scriptable jsArgs = Context.toObject(resWr,mScope);
>         mScope.put("out", mScope, jsArgs);
> mCtx.evaluateString(mScope, jsContent, mScope.getClassName(), 1, null);

You should replace this by:
	private Scriptable mScope = null;
	ResourceWriter resWr = null;
  ...
	Context cx = Context.enter();
	try {
		resWr = new ResourceWriter(new PrintWriter(System.out));
		mScope = cx.initStandardObjects(null);
		Scriptable jsArgs = Context.toObject(resWr,mScope);
		mScope.put("out", mScope, jsArgs);
		cx.evaluateString(mScope, jsContent, mScope.getClassName(), 1, null);
	} finally {
		Context.exit();	
	}

You should always use this Context.enter()/exit() pattern and never 
cache Contex object. A simple way to ensure it is never store Context 
instances in class fields.

Regards, Igor

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