JNI中的GlobalReferences是否可以防止GC清理对象？

Question

According to this and this , GlobalReferences to objects in JNI, keep a reference of the object and all subfields accessible. And it is a memory leak not to manually free it promptly.

What is not clearly stated is if a global reference prevents the object from being GC'd, or the leak is in the reference itself. In other words I am trying to understand if a GlobalReference will stop the object to be GC'ed ever, like if I had an extra reference for it in the Java space, or if the obejct could be GC'd but the leak is in the reference object itself.

I tend to believe is the former, since the weak global reference exists, which according to the docs will let the GC original object die - but I decided to ask to be on the safe side.

Answer 1

if a GlobalReference will stop the object to be GC'ed

Yes, that is the case. The GC is aware of JNI global references and considers them as GC roots.

JNI global references are also exposed in the JVMTI and you can see them in tools like JProfiler.