When JNI_CreateJavaVM throws negative value

Question

when JNI_CreateJavaVM return value is negative value, does it mean
already jvm exits.
i try to grab the jvm using getjvms, the command returns zero code but the number of jvms is 0.
thanks in advance
gvkk

Answer 1

the code is , i am able to successfully compile(1 warning about the exit command)and linking also successfull.when i execute it returns -1 value (JNI_ERR).this code is from forum.i have tried with the code listed in JNI specs it throws the same error.
thanks for your time in advance
#include <jni.h>
main() {
JavaVMOption options[3];
JavaVMInitArgs vm_args;
JavaVM *jvm;
JNIEnv *env;
long result;
jmethodID mid;
jclass cls;
jobjectArray args;
jstring jstr;
options[0].optionString = "-Djava.class.path=.";
options[1].optionString = "-Djava.compiler=NONE";
options[2].optionString = "-verbose:jni";
vm_args.version = JNI_VERSION_1_2;
vm_args.options = options;
vm_args.nOptions = 2;
vm_args.ignoreUnrecognized = JNI_FALSE;
/* Create the Java VM */
result = JNI_CreateJavaVM(&jvm,(void **)&env, &vm_args);
printf("JVM created\n");
if(result == JNI_ERR ) {
printf("Error invoking the JVM");
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");
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);