Re: ArrayIndexOutOfBoundsException in generic.PUTFIELD

Hi

My experience is that the error you are getting is it because some 
method code has an invalid stack, in this case you are removing too many 
items from the stack, the verifier is picking this up and reporting the 
error. I'm not sure but perhaps some code doesn't call 
MethodGen.setMaxStack() after transforming, although I doubt it, because 
if the code were otherwise correct it should have complained of a stack 
overflow.

The problem has to be with the method it is verifying at the time so if 
you can print out which method the verifier is working on and it's 
bytecodes you could go through it and find the problem. The bytecode 
pre-transformation by BCEL should be correct so the problem lies with 
the transformations your code performs.

I'm don't know why this should be a problem with 1.5 and not 1.4.

Hope it helps

Bye Arrin

Razvanica wrote:
> Hello all,
>
> Here's my problem. I am trying to make some network simulations using a tool
> called JiST/SWANS. This simulator has been written for Java 1.4 and, for my
> simulations, I would like to use some 1.5 features, like genericity. 
>
> So what I am trying to do is to compile the original code with the "source
> -1.5" tag instead of the "source -1.4" tag. The problem is that the
> simulator uses bcel to rewrite the bytecode so that JVM could be used for
> simulations. The bcel library in the release doesn't work with the "source
> -1.5" tag so I replace it with bcel-5.2. I made 2 minor modifications to the
> original code :
> - I have added an implementation of getClassPath in a class that implements
> org.apache.bcel.util.Repository. This class just returns null, just like in
> org.apache.bcel.util.ClassLoaderRepository
> - In a class using org.apache.bcel.Repository.lookupClass() I am now
> throwing java.lang.ClassNotFoundException 
>
> These 2 modifications shouldn't change anything as far as I understand the
> application. And when I compile the new code with the "-source 1.4" tag, it
> doesn,t change anything. Everything compiles and works just fine. However,
> when I compile the new code with the "-source 1.5" tag the compilation goes
> smoothly, but, at runtime, the rewriter throws an
> ArrayIndexOutOfBoundsException.
>
>
> This happens every time org.apache.bcel.generic.PUTFIELD.accept is called:
> java.lang.ArrayIndexOutOfBoundsException: -1 
>    at java.util.ArrayList.remove(ArrayList.java:390)
>    at
> org.apache.bcel.verifier.structurals.OperandStack.pop(OperandStack.java:135)
>    at
> org.apache.bcel.verifier.structurals.ExecutionVisitor.visitPUTFIELD(ExecutionVisitor.java:1048)
>    at org.apache.bcel.generic.PUTFIELD.accept(PUTFIELD.java:78)
>
> Does anybody have any idea what happens and if there's something I could do
> to fix this?
>
> Thank you.
>