C语言调用 Java（Linux）

一、书写C文件，模拟JDK中自带的java命令

#include #include #include int main(int argc, char*argv[]) { JavaVM *jvm; JNIEnv *env; JavaVMInitArgs vm_args; JavaVMOption options[1]; jobjectArray applicationArgs; jstring appArg; /* * Setting VM arguments */ vm_args.version = JNI_VERSION_1_2; vm_args.ignoreUnrecognized = JNI_TRUE; vm_args.nOptions = 0; /* * Setting classpath */ char classpath[1024] = "-Djava.class.path="; char *env_classpath = getenv("CLASSPATH"); int mainclass_index = 1; if (argc >= 3 && !strcmp("-classpath", argv[1])) { options[0].optionString = strcat(classpath, argv[2]); vm_args.nOptions++; mainclass_index += 2; } else if (env_classpath) { options[0].optionString = strcat(classpath, env_classpath); vm_args.nOptions++; } if (vm_args.nOptions > 0) { vm_args.options = options; } if (mainclass_index >= argc) { printf("Main class not found, please specify it/n"); return 0; } jint res = JNI_CreateJavaVM(&jvm, (void **)&env, &vm_args); if (res < 0) { printf("Create Java VM error, code = %d/n", res); return -1; } jclass cls = (*env)->FindClass(env, argv[mainclass_index]); if (!cls) { printf("Class %s not found/n", argv[mainclass_index]); return -1; } jmethodID mid = (*env)->GetStaticMethodID(env, cls, "main", "([Ljava/lang/String;)V"); if (!mid) { printf("Method %s of Class %s not found/n", "main", argv[mainclass_index]); return -1; } applicationArgs = (*env)->NewObjectArray(env, argc - mainclass_index - 1, (*env)->FindClass(env, "java/lang/String"), NULL); int i = 0; for (i = mainclass_index + 1; i < argc; i ++) { appArg = (*env)->NewStringUTF(env, argv[i]); (*env)->SetObjectArrayElement(env, applicationArgs, i - mainclass_index - 1, appArg); } (*env)->CallStaticVoidMethod(env, cls, mid, applicationArgs); printf("before destroy/n"); /* * Destroy the JVM. * This is necessary, otherwise if the called method exits, * this program will return immediately. */ (*jvm)->DestroyJavaVM(jvm); printf("after destroy/n"); return 0; }

二、编译，书写makefile文件 ，注意要链接JDK中所自带的jvm.so文件，“-L/sandbox/JAVA2S/jdk1.6.0_16/jre/lib/i386/client/”

all:jvm jvm: gcc -o jvm jvm.c -I/sandbox/JAVA2S/jdk1.6.0_16/include -I/sandbox/JAVA2S/jdk1.6.0_16/include/linux/ -L/sandbox/JAVA2S/jdk1.6.0_16/jre/lib/i386/client/ -ljvm

三、修改.bash_profile文件，设置环境变量，即libjvm.so 所在的路径

export LD_LIBRARY_PATH=/sandbox/JAVA2S/jdk1.6.0_16/jre/lib/i386/client

四、运行命令./jvm -classpath . Test 34 67

结果如下

 

至此，C语言调用Java程序完成

 

参考资料：

http://supermmx.org/blog/20060811_calling_java_from_c_cplusplus