call nonstatic methods from java to cpp using JNI -


i trying call non static method java c++ using jni java code here: 

public class hellojava {   public static void main(string args[])    {      system.out.println("hello world!");      system.out.println("this main function helloworld java class.");   }  public void message() {     system.out.println("call object");  }

}

and c++ code here:

#include <stdio.h> #include <jni.h>   jnienv* create_vm(javavm ** jvm) {  jnienv *env; javavminitargs vm_args; javavmoption options;  options.optionstring = "-djava.class.path=/home/../nonstaticjavamethods/";      //path java source code  vm_args.version = jni_version_1_6; //jdk version. indicates version 1.6 vm_args.noptions = 1; vm_args.options = &options; vm_args.ignoreunrecognized = 0;   int ret = jni_createjavavm(jvm, (void**)&env, &vm_args); if(ret < 0)     printf("\nunable launch jvm\n");      return env; }  int main(int argc, char* argv[]) { jnienv *env; javavm * jvm; env = create_vm(&jvm); if (env == null)     return 1;      //jclass clsh=null; jmethodid midmain = null; jstring square; jclass clsh = env->findclass("helloworld"); jmethodid constructor = env->getmethodid(clsh, "<init>", "void(v)"); jobject object = env->newobject(clsh, constructor);    //obtaining method ids if (clsh != null) {          midmain = env->getmethodid(clsh, "message", "void(v)");            env->callvoidmethod(clsh, midmain, object,null);  } else {     printf("\nunable find requested class\n");        }     //release resources. int n = jvm->destroyjavavm(); return 0;  }  code compiles giving me runtime error. following error

a fatal error has been detected java runtime environment:

 sigsegv (0xb) @ pc=0x00007fdf3f5126bb, pid=11302, tid=140596827092800  jre version: openjdk runtime environment (7.0_55-b14) (build 1.7.0_55-b14) java vm: openjdk 64-bit server vm (24.51-b03 mixed mode linux-amd64 compressed oops) problematic frame: v  [libjvm.so+0x5c46bb]  alloc_object(_jclass*, thread*)+0x1b   failed write core dump. core dumps have been disabled. enable core dumping,      try      "ulimit -c unlimited" before starting java again   error report file more information saved        /home/../nonstaticjavamethods/hs_err_pid11302.log        aborted!

additionally immibis' answer, think call 

jclass clsh = env->findclass("helloworld");

isn't returning anything, class called

public class hellojava

so application seg-faulting in getmethodid() or newobject()


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