Core dump following g++ compilation + link with jni and subsequent execution of application using C++ and Java

Question

I require to execute some arbitrary Java code from within C++. I am utilizing the JNI for this but have encountered an issue. The C++ file compiles fine, however upon execution the following is produced:

A fatal error has been detected by the Java Runtime Environment:

SIGSEGV (0xb) at pc=0xb6f90ffb, pid=10063, tid=3062122240

JRE version: 7.0_10-b18 Java VM: Java HotSpot(TM) Server VM (23.6-b04 mixed mode linux-x86 ) Problematic frame: V [libjvm.so+0x440ffb] JNI_ArgumentPusherVaArg::JNI_ArgumentPusherVaArg(_jmethodID*, char*)+0x1b

Core dump written. Default location: /home/alex/candjava/core or core.10063

An error report file with more information is saved as: /home/alex/candjava/hs_err_pid10063.log

If you would like to submit a bug report, please visit: http://bugreport.sun.com/bugreport/crash.jsp

Aborted (core dumped)

The compilation command:

g++ sample.cpp -o app -I $JAVA_HOME/include -I $JAVA_HOME/include/linux -I $JAVA_HOME/jre/lib/i386/client -L$JAVA_HOME/jre/lib/i386/client -ljvm -Wno-write-strings

where $JAVA_HOME is /usr/lib/jvm/java-7-oracle

The java source:

public class Main{

public void test(){
    System.out.println("HELLO WORLD");
    }
}

The C++ source:

#include <stdio.h>
#include <stdlib.h>
#include <jni.h>
#include <string.h>

int main()
{
    JavaVM *jvm;       /* denotes a Java VM */
    JNIEnv *env;       /* pointer to native method interface */
    JavaVMInitArgs vm_args; /* JDK/JRE 6 VM initialization arguments */
    JavaVMOption* options = new JavaVMOption[1];
    options[0].optionString = "-D java.class.path=/usr/lib/jvm/java-7-oracle/bin";
    vm_args.version = JNI_VERSION_1_6;
    vm_args.nOptions = 1;
    vm_args.options = options;
    vm_args.ignoreUnrecognized = false;
    /* load and initialize a Java VM, return a JNI interface
     * pointer in env */
    JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);
    delete options;
    /* invoke the Main.test method using the JNI */
    jclass cls = env->FindClass("Main");
    jmethodID mid = env->GetStaticMethodID(cls, "test", "(I)V");
    env->CallStaticVoidMethod(cls, mid, 100);
    /* We are done. */
    jvm->DestroyJavaVM();

}

Any help with this would be much appreciated!

Answer 1

You aren't checking any error returns from the JNI functions. You need to check for errors.

Answer 2

jmethodID mid = env->GetStaticMethodID(cls, "test", "(I)V");

says your function is void and you have integer as argument. but you are not sending any integer argument it must be as follows

jmethodID mid = env->GetStaticMethodID(cls, "test", "()V");

Answer 3

there are some obvious errors in your source code.

1. the test method in the Main class should be static
2. the test parameter should be int
3. the java.class.path parameter is ridiculous

I also have the third problem. change the option -Djava.class.path=/Path-to-your-class-file-directory will be ok. (Mine is "-Djava.class.path=.")