java_wrapper->java_obj = NULL;
enumerate_remove_java_obj(JSJHashEntry *he, PRIntn i, void *arg){    JNIEnv *jEnv = (JNIEnv*)arg;    jobject java_obj;    java_obj = (jobject)he->key;    (*jEnv)->DeleteGlobalRef(jEnv, java_obj);    return HT_ENUMERATE_REMOVE;}