JNI AttachCurrentThread NULLs the jenv

Posted by Damg on Stack Overflow See other posts from Stack Overflow or by Damg
Published on 2010-04-16T09:46:50Z Indexed on 2010/04/16 9:53 UTC
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delphi

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java

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jni

Hello all,

I'm currently in the process of adding JNI functionality into a legacy delphi app. In a single-threaded environment everything works fine, but as soon as I move into multi-threaded environment, things start to become hairy.

My problem is that calling JavaVM^.AttachCurrentThread( JavaVM, @JEnv, nil ); returns 0, but puts the JEnv pointer to nil. I have no idea why jvm.dll should return a NULL pointer.

Is there anything I am missing?

Thank you in advance -- damg

PS:
* Environment: WinXP + JDK 1.6
* Using JNI.pas from http://www.pacifier.com/~mmead/jni/delphi/

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