windows C启动JDK11的JVM

本示例使用的jdk为 adopt-openj9-11.0.10
核心API是调用windows的GetProcAddress

hjvmlib = loadJVMLibrary();
createJavaVM = (CreateJavaVM_t) GetProcAddress(hjvmlib, "JNI_CreateJavaVM");
status = (*createJavaVM)(&jvm, (void **) &env, &vm_args);

这个方法能调起dll的库函数
dll导入

static HINSTANCE loadJVMLibrary(void)
{
   HINSTANCE h1, h2;
   char msvcdll[MAX_PATH] = /** JDK目录 **/;
   char javadll[MAX_PATH] = /** JDK目录 **/";

   //GetPublicJREHome(msvcdll, MAX_PATH);
   strcpy(javadll, msvcdll);
   strncat(msvcdll, "\\bin\\msvcp140.dll", MAX_PATH - strlen(msvcdll));
   msvcdll[MAX_PATH - 1] = '\0';
   strncat(javadll, "\\bin\\j9vm\\jvm.dll", MAX_PATH - strlen(javadll));
   javadll[MAX_PATH - 1] = '\0';

   h1 = LoadLibrary(msvcdll);
   if (h1 == NULL)
   {
      fprintf(stderr, "Can't load library msvcp140.dll\n");
      exit(1);
   }

   h2 = LoadLibrary(javadll);
   if (h2 == NULL)
   {
      fprintf(stderr, "Can't load library jvm.dll\n");
      exit(1);
   }
   return h2;
}

配置jvm参数

JavaVMOption options[2];
   JavaVMInitArgs vm_args;
   JavaVM *jvm;
   JNIEnv *env;
   long status;

   jclass class_Welcome;
   jclass class_String;
   jobjectArray args;
   jmethodID id_main;

#ifdef _WINDOWS
   HINSTANCE hjvmlib;
   CreateJavaVM_t createJavaVM;
#endif

   options[0].optionString = "-Djava.class.path=.";
   //options[1].optionString = "-Dfile.encoding=UTF-8";

   memset(&vm_args, 0, sizeof(vm_args));
   vm_args.version = JNI_VERSION_10;
   vm_args.nOptions = 1;
   vm_args.options = options;

测试代码
2个java

package com.ccand99;

public class Welcome {
    public Welcome() {
    }

    public static void main(String[] args) {
        var china = new China();
        china.printf();
    }
}
package com.ccand99;

public class China {

    public void printf(){
        System.out.println("中国");
    }
}

c执行Weclome,注意目录=包名

if (status == JNI_ERR)
   {  
      fprintf(stderr, "Error creating VM\n");
      return 1;
   }

   class_Welcome = (*env)->FindClass(env, "com/ccand99/Welcome");
   id_main = (*env)->GetStaticMethodID(env, class_Welcome, "main", "([Ljava/lang/String;)V");

   class_String = (*env)->FindClass(env, "java/lang/String");
   args = (*env)->NewObjectArray(env, 0, class_String, NULL);
   (*env)->CallStaticVoidMethod(env, class_Welcome, id_main, args);

   (*jvm)->DestroyJavaVM(jvm);

   return 0;

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