jni jnienv DeleteWeakGlobalRef example c c++ java

DeleteWeakGlobalRef

void DeleteWeakGlobalRef(JNIEnv *env, jweak obj);

Delete the VM resources needed for the given weak global reference.

LINKAGE:

Index 227 in the JNIEnv interface function table.

SINCE:

JDK/JRE 1.2

Example - DeleteWeakGlobalRef

JNIEXPORT void JNICALL
 Java_mypkg_MyCls_f(JNIEnv *env, jobject self)
 {
     static jclass myCls2 = NULL;
     if (myCls2 == NULL) {
         jclass myCls2Local =
             (*env)->FindClass(env, "mypkg/MyCls2");
         if (myCls2Local == NULL) {
             return; /* can't find class */
         }
         myCls2 = NewWeakGlobalRef(env, myCls2Local);
         if (myCls2 == NULL) {
             return; /* out of memory */
         }
     }
     ... /* use myCls2 */

 // After processing is done.

 DeleteWeakGlobalRef(env, myCls2Local);

}