src/hotspot/share/runtime/jniHandles.cpp

*** 139,148 ****
--- 139,153 ----
      jweak_ref(handle) = deleted_handle();
    }
  }
  
  
+ bool JNIHandles::is_global_weak_cleared(jweak handle) {
+   assert(is_jweak(handle), "not a weak handle");
+   return guard_value<false>(jweak_ref(handle)) == NULL;
+ }
+ 
  void JNIHandles::oops_do(OopClosure* f) {
    f->do_oop(&_deleted_handle);
    _global_handles->oops_do(f);
  }