Can't create JVM from JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);

Question

I'm new in using JNI. When i compile the C program that invoke the JAVA program, everthing goes fine. I can obtain the the "exe" from the compilation.
But when i run the "exe" file it display "can't create Java VM". Here is the part of the code in C program:
........//other code
JNI_VERSION_1_2
JavaVMInitArgs vm_args;
JavaVMOption options[1];
options[0].optionString =
"-Djava.class.path=" USER_CLASSPATH;
vm_args.version = 0x00010002;
vm_args.options = options;
vm_args.nOptions = 1;
vm_args.ignoreUnrecognized = JNI_TRUE;
/* Create the Java VM */
res = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args);
if (res < 0) {
fprintf(stderr, "Can't create Java VM\n");
exit(1);
.......//other code
I'm using JDK1.3, and windows ME.
Can anyone tell me the problem?

Answer 1

I think you need to get the address of the create function from the jvm.dll at runtime and call that: this works for me:
     HINSTANCE handle;
     JavaVMOption options[5];
     char JREHome[MAX_PATH];
     char JVMPath[MAX_PATH];                                        
     char classpathOption[MAX_PATH];
     char librarypathOption[MAX_PATH];
     if(!GetPublicJREHome(JREHome, MAX_PATH))
          LogError("Could not locate JRE");
          abort();
     strcpy(JVMPath,JREHome);
     strcat(JVMPath,"\\bin\\client\\jvm.dll");
    if ((handle=LoadLibrary(JVMPath))==0)
          LogError("Error loading: %s", JVMPath);
          abort();
    CreateJavaVM_t pfnCreateJavaVM=(CreateJavaVM_t)GetProcAddress(handle,"JNI_CreateJavaVM");
    if (pfnCreateJavaVM==0)
          LogError("Error: can't find JNI interfaces in: %s",JVMPath);
          abort();
     strcpy(classpathOption,"-Djava.class.path=");
     strcat(classpathOption,dir);
     strcat(classpathOption,";");
     strcat(classpathOption,JREHome);
     strcat(classpathOption,"\\lib");
     strcat(classpathOption,";");
     strcat(classpathOption,JREHome);
     strcat(classpathOption,"\\lib\\comm.jar");
     strcpy(librarypathOption,"-Djava.library.path=");
     strcat(librarypathOption,JREHome);
     strcat(librarypathOption,"\\lib");
     OutputDebugString("classpath option=");
     OutputDebugString(classpathOption);
     OutputDebugString("\n");
     OutputDebugString("librarypath option=");
     OutputDebugString(librarypathOption);
     OutputDebugString("\n");
     options[0].optionString=classpathOption;     
     options[1].optionString=librarypathOption;     
     options[2].optionString="vfprintf";
     options[2].extraInfo=_vfprintf_;
     options[3].optionString="exit";
     options[3].extraInfo=_exit_;
     options[4].optionString="abort";
     options[4].extraInfo=_abort_;
    vmArgs.version  = JNI_VERSION_1_2;
    vmArgs.nOptions = 5;
    vmArgs.options  = options;
    vmArgs.ignoreUnrecognized = false;
    if(pfnCreateJavaVM(&jvm,(void**)&env, &vmArgs)!=0)
          LogError("Could not create VM");
          abort();
     }