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class HelloWorld { 
public native void displayHelloWorld();←左方的native型態是通知Java這個函數會使用到外部函數 
 
static { 
System.loadLibrary("hello"); ←左方的程式碼代表我要載入hello.dll的動態連結，hello.dll的製作我在稍後會做介紹 
} 
 
public static void main(String[] args) { 
new HelloWorld().displayHelloWorld(); 
} 
}

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#include 
#include "HelloWorld.h" 
#include 
 
JNIEXPORT void JNICALL 
Java_HelloWorld_displayHelloWorld(JNIEnv *env, jobject obj) 
{ 
printf("HelloWorld"); 
return; 
}

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/* DO NOT EDIT THIS FILE - it is machine generated */ #include 
/* Header for class HelloWorld */ #ifndef _Included_HelloWorld #define _Included_HelloWorld 
#ifdef __cplusplus extern "C" { #endif 
/* 
* Class: HelloWorld 
* Method: displayHelloWorld 
* Signature: ()V 
*/ 
JNIEXPORT void JNICALL Java_HelloWorld_displayHelloWorld 
(JNIEnv *, jobject); 
#ifdef __cplusplus } #endif 
#endif

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#include <jni.h>
 
#include <stdafx.h>
 
#include "WordWriter.h"
 
#include <WordServiceImpl.h>
 
JNIEXPORT jboolean JNICALL 
Java_WordServiceImpl_OpenDocFile (JNIEnv *env, jobject jobj, jstring fileName){
  jboolean rs = false;
  jclass klass = env->GetObjectClass(fileName);
  jmethodID getBytes = env->GetMethodID(klass, "getBytes", "(Ljava/lang/String;)[B");
  jvalue arg;
  arg.l = env->NewStringUTF("Big5");
  jbyteArray chs = (jbyteArray) env->CallObjectMethodA(fileName, getBytes, &arg);
  int len = env->GetArrayLength(chs);
  jbyte* msgP = env->GetByteArrayElements(chs, 0);
  char* buf = new char[len + 1];
  buf[len] = '\0';
  for (int i = 0; i < len; ++i)
    buf[i] = msgP[i];
  env->ReleaseByteArrayElements(chs, msgP, JNI_ABORT);
  printf("Message is: %s\n", buf);  
 
  HINSTANCE dllInstance = LoadLibrary("WordCall.dll");
  (FARPROC &)OpenDocFile = GetProcAddress( dllInstance,"OpenDocFile");
  rs = OpenDocFile(buf);
  delete[] buf; 
  return false;
}