JNI error when trying to access the EXTRA_ADDRESS_BOOK_INDEX field

Question

I am trying to access the EXTRA_ADDRESS_BOOK_INDEX constant using JNI:

JNIEXPORT jint JNICALL JNI_OnLoad(JavaVM* vm, void* reserved) {
    JNIEnv* env = nullptr;
    vm->GetEnv(reinterpret_cast<void**>(&env), JNI_VERSION_1_6);
    jclass clazz = env->FindClass("android/provider/ContactsContract$Data");
    jfieldID fieldID = env->GetStaticFieldID(clazz, "EXTRA_ADDRESS_BOOK_INDEX", "Ljava/lang/String;");
    jobject field = env->GetStaticObjectField(clazz, fieldID);
}

The GetStaticObjectField method crashes with an error:

java_vm_ext.cc:534] JNI DETECTED ERROR IN APPLICATION: static jfieldID 0x6fd191b0 not valid for class java.lang.Class<android.provider.ContactsContract$Data>

On the other hand if I try to access the VISIBLE_CONTACTS_ONLY field on the same class, everything works as expected:

jfieldID fieldID = env->GetStaticFieldID(clazz, "VISIBLE_CONTACTS_ONLY", "Ljava/lang/String;");

Any clues what I might be doing wrong?

Answer 1

So I tried to solve it and getting the same error, then I searched the source code of the final class ContactsContract and found that the field EXTRA_ADDRESS_BOOK_INDEX is not declared in the nested class Data but in a nested interface called ContactCounts.

So the solution is to replace "android/provider/ContactsContract$Data" by "android/provider/ContactsContract$ContactCounts"