java JNI: C 语言调用 Java 方法示例详解编程语言

#include <jni.h> 
#include <stdio.h> 
#include <stdlib.h> 
 
#include <wchar.h> /* include the file to support unicode function */ 
 
const char* 
DispatchStatus(int status) 
{ 
    switch (status) { 
        case JNI_OK: 
            return /"success/"; 
            break; 
        case JNI_ERR: 
            return /"unknown error/"; 
            break; 
        case JNI_EDETACHED: 
            return /"thread detached from the VM/"; 
            break; 
        case JNI_EVERSION: 
            return /"JNI version error/"; 
            break; 
        default: 
            return __FILE__ /": unknow error/"; 
            break; 
    } 
} 
 
void 
ArrayTest(JNIEnv* env) 
{ 
    int i = 1; 
    jintArray array = (*env)-> NewIntArray(env, 10); 
 
    for(; i<= 10; i++) 
        (*env)->SetIntArrayRegion(env, array, i-1, 1, &i); 
 
    /* 获取数组对象的元素个数 */ 
    int len = (*env)->GetArrayLength(env, array); 
    /* 获取数组中的所有元素 */ 
    jint* elems = (*env)-> GetIntArrayElements(env, array, 0); 
    for(i=0; i< len; i++) 
        printf(/"ELEMENT %d IS %d//n/", i, elems[i]); 
} 
 
int 
main(int argc, const char** argv) 
{ 
    jint status = JNI_OK; 
    JavaVM* jvm = (JavaVM*)0; 
    JNIEnv* env = (JNIEnv*)0; 
 
    JavaVMInitArgs vm_args; 
 
    vm_args.version = JNI_VERSION_1_4; 
    vm_args.options = (JavaVMOption*)0; 
    vm_args.nOptions = 0; 
    vm_args.ignoreUnrecognized = JNI_FALSE; 
 
    status = JNI_GetDefaultJavaVMInitArgs(&vm_args); 
    if (0 != status) { 
        printf(/"%s//n/", DispatchStatus(status)); 
        return EXIT_FAILURE; 
    } 
 
    status = JNI_CreateJavaVM(&jvm, (void**)&env, &vm_args); 
    if (0 != status) { 
        printf(/"test: %s//n/", DispatchStatus(status)); 
        return EXIT_FAILURE; 
    } 
    printf(/"//r//n===== Array testing =====//r//n/"); 
    ArrayTest(env); 
 
    printf(/"test: success//n/"); 
    if(jvm) 
    (*jvm)->DestroyJavaVM(jvm); 
    return EXIT_SUCCESS; 
} 
//该片段来自于http://outofmemory.cn