JNI调用

来源：互联网发布：淘宝摄影师兼职编辑：程序博客网时间：2024/06/06 00:09

http://blog.csdn.net/xdonx/article/details/8450427

http://blog.chinaunix.net/uid-10275706-id-3241480.html

1.新建文件夹test.

2.在test文件夹中放置文件HelloWorld.java：

package test;public class HelloWorld {    public static void main(String[] args) {        System.loadLibrary("HelloWorld");        printHello();    }    public static native final void printHello();}

3.编译HelloWorld.java:

javac test/HelloWorld.java

4.在test文件夹中放置文件HelloWorld.cpp:

#include <iostream>#include <jni.h>using namespace std;static int android_print(JNIEnv * env, jclass clazz) {    cout<<"helloworld"<<endl;}static JNINativeMethod gMethods[] = {    {"printHello", "()V", (void*)android_print},};jint JNI_OnLoad(JavaVM* vm, void* reserved) {    JNIEnv* env = NULL;    if (vm->GetEnv((void**) &env, JNI_VERSION_1_6) != JNI_OK)        return -1;    jclass clazz = (env)->FindClass("test/HelloWorld");    if((env)->RegisterNatives(clazz, gMethods, 1)< 0)        return -1;    return JNI_VERSION_1_6;}

5.编译HelloWorld.cpp:

g++ test/HelloWorld.cpp -fPIC -shared -o test/libHelloWorld.so -I /usr/lib/jvm/java-7-openjdk-i386/include/

6.设置环境变量:

export LD_LIBRARY_PATH=./test

7.目录结构:

./test:
HelloWorld.class HelloWorld.cpp HelloWorld.java libHelloWorld.so

8.运行:

java test.HelloWorld
helloworld

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