I guess the implementation boolean android.util.Log.isLoggable(java.lang.String, int) should located in /system/lib64/liblog.so.

But when run on Android U(14) it alerts as below:

04-29 01:17:36.745  2744  2744 F DEBUG   : Abort message: 'No pending exception expected: java.lang.UnsatisfiedLinkError: No implementation found for boolean android.util.Log.isLoggable(java.lang.String, int) (tried Java_android_util_Log_isLoggable and Java_android_util_Log_isLoggable__Ljava_lang_String_2I) - is the library loaded, e.g. System.loadLibrary?
04-29 01:17:36.745  2744  2744 F DEBUG   :   at boolean android.util.Log.isLoggable(java.lang.String, int) (Log.java:-2)
04-29 01:17:36.745  2744  2744 F DEBUG   :   at void android.app.Instrumentation.<clinit>() (Instrumentation.java:103)