Subj : memory error causing undefined value has no properties
To   : netscape.public.mozilla.jseng
From : tryung@polyu.edu.hk (wyx)
Date : Thu Jan 23 2003 06:55 pm

hello all,
I use rhino and written a js to calculate some statistic.
In my js file, I used array of javascript object
and also a few array of string and integer.

So I have a lof of "for/loop" as I need to iterate the values.

originally, I use "for(var in..)" for each array.
On SunBlade 100 with jdk 1.3.1_04-b02, the js program works fine 
and no error.

however, after I deployed my js to E280 with jdk 1.3.1-b24, it will
some time show the "undefined value has no properties" error.
But this error seems showing randomly, becuase I apply the same set of data,
sometime it will show the error, sometime it will not.

And lastly, I added some system.out.println in the js file.
and I found that in the "for(var in...)" loop, sometime it will skip
some index and then error thrown.
eg. 
idx=151, print something
idx=153, print something

then error thrown. idx=152 was skipped.

Then after a pain investigation, I replace all the
"for(var in...)" loop by "for(var x=0; x<total; x++)"
then the "undefined value..." error never show up.

I use interpret mode (optimization=-1).

But so bad is that, there is some memory reference error.
I don't know why sometime, some interger value will be refered
with some garbage. eg. 4.:
So I added the follow line to check it.

if( parseInt(itemTCount[tt].tCount) !=  itemTCount[tt].tCount)
	java.lang.System.out.println("Error item:["+itemTCount[tt].tCount +"]");

What I expect is some string print out.
But so strange that it print something like
Error item:[130]

so....if the value is 130, then how can it be printed out?

so..I think there maybe some memory reference error for rhino when
it need to do complicated calculation or has many objects in the scope.

hope some can help!

yung

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