Can't create Java VM ?

Question

Hi,
I tried to invoke JavaVM in C. And use the example from http://java.sun.com/docs/books/tutorial/native1.1/invoking/invo.html.
But when runed it after compiled it in Win32 with VC6.
It just can't create the VM. The following is the source:
========================================
#include <jni.h>
#ifdef _WIN32
#define PATH_SEPARATOR ';'
#else /* UNIX */
#define PATH_SEPARATOR ':'
#endif
#define USER_CLASSPATH "." /* where Prog.class is */
main() {
     JNIEnv *env;
     JavaVM *jvm;
     jint res;
     jclass cls;
     jmethodID mid;
     jstring jstr;
     jobjectArray args;
     char classpath[1024];
     JavaVMInitArgs vm_args;
     JavaVMOption options[4];
     options[0].optionString = "-Djava.compiler=NONE"; /* disable JIT */
     options[1].optionString = "-Djava.class.path=.";                     /* user classes */
     options[2].optionString = "-Djava.library.path=.";                /* set native library path */
     options[3].optionString = "-verbose:jni"; /* print JNI-related messages */
     vm_args.version = JNI_VERSION_1_2;
     vm_args.options = options;
     vm_args.nOptions = 4;
     vm_args.ignoreUnrecognized = 1;
JNI_GetDefaultJavaVMInitArgs(&vm_args);
/* Append USER_CLASSPATH to the end of default system class path */
//sprintf(classpath, "%ls%c%s", vm_args.classpath, PATH_SEPARATOR, USER_CLASSPATH);
//vm_args.classpath = casspath;
/* Create the Java VM */
res = JNI_CreateJavaVM(&jvm, &env, &vm_args);
if (res < 0) {
fprintf(stderr, "Can't create Java VM\n");
exit(1);
cls = (*env)->FindClass(env, "Prog");
if (cls == 0) {
fprintf(stderr, "Can't find Prog class\n");
exit(1);
mid = (*env)->GetStaticMethodID(env, cls, "main", "([Ljava/lang/String;)V");
//mid = (*env)->GetMethodID(cls, "Yup","(I)Ljava/lang/String;"); /* Search the Method of class*/
if (mid == 0) {
fprintf(stderr, "Can't find Prog.main\n");
exit(1);
jstr = (*env)->NewStringUTF(env, " from C!");
if (jstr == 0) {
fprintf(stderr, "Out of memory\n");
exit(1);
args = (*env)->NewObjectArray(env, 1, (*env)->FindClass(env, "java/lang/String"), jstr);
if (args == 0) {
fprintf(stderr, "Out of memory\n");
exit(1);
(*env)->CallStaticVoidMethod(env, cls, mid, args);
(*jvm)->DestroyJavaVM(jvm);
========================================
Would you please to tell me why it failed and please show me a simple example ?
Best regards,
Eric

Answer 1

I have the same problem,
/* Create the Java VM */
res = JNI_CreateJavaVM(&jvm, (void **)&env,
nv, &vm_args);
if (res < 0) {
fprintf(stderr, "Can't create Java VM: %d\n",
%d\n", res);
exit(1);
res is -1...but I'm not using windows, I'm using Linux
and Solaris...Hi there,
I also have problem calling JNI_CreateJavaVM on Linux (returns -1). Have you been able to solve this in the meantime?