According to Sun documentation NULL is a allowed to call DeleteLocalRef() with a NULL argument. The GCJ jni implementation exits (Aborted) in this case.
From: http://java.sun.com/docs/books/jni/html/exceptions.html 6.1.2 A Utility Function Passing NULL to DeleteLocalRef is a no-op, which is an appropriate action if FindClass fails and returns NULL. -- Summary: jniEnv->DeleteLocalRef (null) fails Product: gcc Version: 4.0.2 Status: UNCONFIRMED Severity: normal Priority: P3 Component: libgcj AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: hakan dot hjort at gmail dot com GCC target triplet: i386-redhat-linux http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28178
