Calling java API from c/c++ in Android -

i trying call java api c/c++. wrote code this:

#include <stdio.h> #include <stdlib.h> #include <unistd.h> #incldue <jni.h> int main() {     javavm *vm;    jnienv *env;    javavminitargs vm_args;    vm_args.version = jni_version_1_2;    vm_args.noptions = 0;    vm_args.ignoreunrecognized = 1;      // construct vm     jint res = jni_createjavavm(&vm, &env, &vm_args);      jclass cls = env->findclass("classname");     jmethodid mid = env->getstaticmethodid(cls, "methodname", "(i)v");     env->callstaticvoidmethod(cls, mid, 100);       /* done. */     vm->destroyjavavm(); } 

on runtime throws error failed create jniinvocation instance before using jni invocation api
suggestion ?
thanks.