Simple example of using the Java Native Interface(JNI)

按以下步骤可以在Java文件中编写native方法.

1. 创建HelloWorld.java文件(declares the native method);

class HelloWorld {

static {
System.loadLibrary("HelloWorld");
}

private native void print();

public static void main(String[] args) {
new HelloWorld().print();
}
}

2. 编译"javac HelloWorld.java";

3. 执行"javah -jni HelloWorld"生成HelloWorld.h;

4. 创建HelloWorld.c;

#include <jni.h>
#include <stdio.h>
#include "HelloWorld.h"

JNIEXPORT void JNICALL
Java_HelloWorld_print(JNIEnv *env, jobject obj)
{
printf("Hello World!n");
return;
}

5. 在Redhat5.8中编译HelloWorld.c,生成HelloWorld.so;

gcc -c -fPIC -I/scratch/luwang/jdk6/include HelloWorld.c
gcc -shared -o libHelloWorld.so HelloWorld.o

6. 设置LD_LIBRARY_PATH;

LD_LIBRARY_PATH=.:${LD_LIBRARY_PATH}; java HelloWorld

或

java -Djava.library.path=. HelloWorld

参考：

http://www.java-tips.org/other-api-tips/jni/simple-example-of-using-the-java-native-interface.html

http://ubuntuforums.org/showthread.php?t=1942105