i m getting java.lang.UnsatisfiedLinkError while trying to run a ndk example?

i m just trying to run ndk example code from below link. How do I handle calls to AudioTrack from jni without crashing?

But getting the above exception.The below is the detailed log.

E/AndroidRuntime(15523): FATAL EXCEPTION: Thread-9
E/AndroidRuntime(15523): java.lang.UnsatisfiedLinkError: audioFunc
E/AndroidRuntime(15523):        at com.audio.demo.MainActivity.audioFunc(Nativ开发者_开发问答e Method)
E/AndroidRuntime(15523):        at com.audio.demo.MainActivity$1.run(MainActivity.java:35)
E/AndroidRuntime(15523):        at java.lang.Thread.run(Thread.java:1096)
W/ActivityManager( 2486):   Force finishing activity com.audio.demo/.MainActivity

i m stucked with this exception can anybody help me?