How to set a breakpoint in <clinit> using JVMTI

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darthmind@gmail.com - 25 Apr 2006 19:26 GMT

Does anyone know how to get a Method or Constructor object for <clinit>
(which we know
isn't either), to be able use it in JVMTI's SetBreakpoint() in order to
set a breakpoint in
<clinit>? Or how to otherwise obtain a jmethodID for <clinit>?

tia

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Chris Uppal - 26 Apr 2006 11:14 GMT

> Does anyone know how to get a Method or Constructor object for <clinit>
> (which we know
> isn't either), to be able use it in JVMTI's SetBreakpoint() in order to
> set a breakpoint in
> <clinit>? Or how to otherwise obtain a jmethodID for <clinit>?

As far as the JVM is concerned, <clinit> is just another static method (albeit
one with special rules about how and when it must[n't] be called). So I
imagine that you can get a handle on the method in just the same was as you
would for any other static method. I haven't tried it with JVMTI, but in JNI
calling
GetStaticMethodID(jclass, '<clinit>', '()V').
returns an apparently valid method ID.

-- chris

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darthmind@gmail.com - 26 Apr 2006 13:41 GMT

<clinit> is a special method. And, no, Class.getMethods() and the like
explicitly exclude <clinit>. The problem with GetStaticMethodID() is
that it initializes an uninitialized class, which is not desired in
this case.

Anyone else have any other thoughts?

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How to set a breakpoint in <clinit> using JVMTI

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