java.lang.exceptionininitializererror in android ndk -

i'm trying simple addition program in android ndk. i'm getting following exception -

java.lang.exceptionininitializererror 

java file-

public class mainactivity extends activity { private native void mymethod(int a,int b);       @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);         mymethod(4,5);     }      static {         system.loadlibrary("native"); // here i'm getting exception     }  } 

android.mk

local_path := $(call my-dir)  include $(clear_vars) local_ldlibs := -llog local_module    := native local_src_files := native.c include $(build_static_library)  

native.c

#include <jni.h> #include <string.h> #include <android/log.h>  #define debug_tag "ndksetupactivity"  void java_com_example_additionndk_mainactivity_mymethod(jnienv * env, jobject this, jint a,jint b) {     jint c=a+b;     __android_log_print(android_log_debug, debug_tag, "addition: %d", c); } 

i ran error once when running sample ndk (hello-jni). it's because android sdk version not compatible (default of example 1.5). try switch compatible sdk , modifiy manifest . case haven't build .c .so. use ndk-build cygwin64.