Re: GTK peer switching JNIEnv *?

[Archie Cobbs]

Robert Lougher wrote:
> It would be an interesting question to ask if JNI code
> should expect the JNIEnv* to be different for different threads. 
> Opinions?

Stop the nonsense! :-)

The idea that there is anything other than a 1:1 pairing between
threads and JNIEnv * pointers is crazy^H^H^H^H^Hincorrect. Quoting:

  http://java.sun.com/j2se/1.4.2/docs/guide/jni/spec/design.html

The JNI interface pointer is only valid in the current thread. A native 
method, therefore, must not pass the interface pointer from one thread to 
another. A VM implementing the JNI may allocate and store thread-local data 
in the area pointed to by the JNI interface pointer.

Native methods receive the JNI interface pointer as an argument. The VM is 
guaranteed to pass the same interface pointer to a native method when it 
makes multiple calls to the native method from the same Java thread. 
However, a native method can be called from different Java threads, and 
therefore may receive different JNI interface pointers.

-Archie

__________________________________________________________________________
Archie Cobbs      *        CTO, Awarix        *      http://www.awarix.com