Java监听键盘鼠标全局事件

转自：http://dengpeng.sensorapp.net/?p=495

标准的Java键盘事件监听器(KeyListener)和鼠标事件监听器(MouseListener)只能在该Java程序聚焦的时候监听事件。要想让你的Java程序能够在系统后台跟踪全局键盘和鼠标事件，那就需要使用JNI(Java Native Interface)来创建一个钩子监听操作系统的事件了。本文只讨论，Java程序与Windows操作系统的交互，如果你知道如何实现Java监听Linux事件，请留言，谢谢。开发运行环境：Windows XP SP3, Java 1.6_15, Eclipse 3.5

直接上代码

SysHook.cpp:

#include <windows.h>
#include "SysHook.h"
#include <jni.h>

HINSTANCE hInst = NULL;

JavaVM * jvm = NULL;
jobject hookObj_kb = NULL;
jobject hookObj_ms = NULL;
jobject g_kl = NULL;

jmethodID processKeyID_kb = NULL;
jmethodID processKeyID_ms = NULL;
DWORD hookThreadId = 0;

LONG     g_mouseLocX = -1;     // x-location of mouse position
LONG     g_mouseLocY = -1;     // y-location of mouse position

extern "C"
BOOL APIENTRY DllMain( HINSTANCE _hInst, DWORD reason, LPVOID reserved)
{
 switch (reason)
 {
 case DLL_PROCESS_ATTACH:
 printf ( "C++: DllMain - DLL_PROCESS_ATTACH.\n" );
 hInst = _hInst;
 break ;
 default :
 break ;
 }

return TRUE;
}

LRESULT CALLBACK MouseTracker( int nCode, WPARAM wParam, LPARAM lParam)
{
 JNIEnv * env;
 KBDLLHOOKSTRUCT * p = (KBDLLHOOKSTRUCT *)lParam;

 if (jvm->AttachCurrentThread(( void **)&env, NULL) >= 0)
 {

 if (nCode==HC_ACTION)
 {
 MOUSEHOOKSTRUCT* pStruct = (MOUSEHOOKSTRUCT*)lParam;
 if (pStruct->pt.x != g_mouseLocX || pStruct->pt.y != g_mouseLocY)
 {
 env->CallVoidMethod(hookObj_ms, processKeyID_ms, (jint)pStruct->pt.x,(jint)pStruct->pt.y, g_kl);
 g_mouseLocX = pStruct->pt.x;
 g_mouseLocY = pStruct->pt.y;
 }

 }

 }
 else
 {
 printf ( "C++: LowLevelKeyboardProc - Error on the attach current thread.\n" );
 }

 return CallNextHookEx(NULL, nCode, wParam, lParam);
}

LRESULT CALLBACK LowLevelKeyboardProc( int nCode, WPARAM wParam, LPARAM lParam)
{
 JNIEnv * env;
 KBDLLHOOKSTRUCT * p = (KBDLLHOOKSTRUCT *)lParam;

 if (jvm->AttachCurrentThread(( void **)&env, NULL) >= 0)
 {
 switch (wParam)
 {
 case WM_KEYDOWN:
 case WM_SYSKEYDOWN:
 env->CallVoidMethod(hookObj_kb, processKeyID_kb, (jboolean)TRUE, p->vkCode,g_kl);
 break ;
 case WM_KEYUP:
 case WM_SYSKEYUP:
 env->CallVoidMethod(hookObj_kb, processKeyID_kb, (jboolean)FALSE, p->vkCode,g_kl);
 break ;
 default :
 break ;
 }
 }
 else
 {
 printf ( "C++: LowLevelKeyboardProc - Error on the attach current thread.\n" );
 }

 return CallNextHookEx(NULL, nCode, wParam, lParam);
}

void MsgLoop()
{
 MSG message;
 while (GetMessage(&message, NULL, 0, 0))
 {
 TranslateMessage(&message);
 DispatchMessage(&message);
 }
}

JNIEXPORT void JNICALL Java_SysHook_registerHook(JNIEnv * env, jobject obj,jobject kl)
{
 HHOOK hookHandle_ms = SetWindowsHookEx(WH_MOUSE_LL, MouseTracker, hInst, 0);
 HHOOK hookHandle_kb = SetWindowsHookEx(WH_KEYBOARD_LL, LowLevelKeyboardProc, hInst, 0);

 g_kl = kl;

 if (hookHandle_ms == NULL)
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Hook failed!\n" );
 return ;
 }
 else
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Hook successful\n" );
 }

 if (hookHandle_kb == NULL)
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Hook failed!\n" );
 return ;
 }
 else
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Hook successful\n" );
 }

 hookObj_kb = env->NewGlobalRef(obj);
 jclass cls_kb = env->GetObjectClass(hookObj_kb);
 processKeyID_kb = env->GetMethodID(cls_kb, "processKey" , "(ZILGlobalEventListener;)V" );

 hookObj_ms = env->NewGlobalRef(obj);
 jclass cls_ms = env->GetObjectClass(hookObj_ms);
 processKeyID_ms = env->GetMethodID(cls_ms, "mouseMoved" , "(IILGlobalEventListener;)V" );

 env->GetJavaVM(&jvm);
 hookThreadId = GetCurrentThreadId();

 MsgLoop();

 if (!UnhookWindowsHookEx(hookHandle_kb))
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Unhook failed\n" );
 }
 else
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Unhook successful\n" );
 }

 if (!UnhookWindowsHookEx(hookHandle_ms))
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Unhook failed\n" );
 }
 else
 {
 printf ( "C++: Java_SysHook_registerKeyHook - Unhook successful\n" );
 }
}

JNIEXPORT void JNICALL Java_SysHook_unRegisterHook(JNIEnv *env, jobject object)
{
 if (hookThreadId == 0)
 return ;

 printf ( "C++: Java_SysHook_unRegisterKeyHook - call PostThreadMessage.\n" );
 PostThreadMessage(hookThreadId, WM_QUIT, 0, 0L);
}

SysHook.h:

/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class SysHook */

#ifndef _Included_SysHook
#define _Included_SysHook
#ifdef __cplusplus
extern "C" {
#endif
/*
 * Class:     SysHook
 * Method:    registerHook
 * Signature: (LGlobalEventListener;)V
 */
JNIEXPORT void JNICALL Java_SysHook_registerHook  (JNIEnv *, jobject, jobject);

/*
 * Class:     SysHook
 * Method:    unRegisterHook
 * Signature: ()V
 */
JNIEXPORT void JNICALL Java_SysHook_unRegisterHook  (JNIEnv *, jobject);

#ifdef __cplusplus
}
#endif
#endif

KeyboardEventListener.java

import java.util.*;

public interface KeyboardEventListener extends EventListener {
 public void GlobalKeyPressed(KeyboardEvent event);

 public void GlobalKeyReleased(KeyboardEvent event);
}

class KeyboardEvent extends EventObject {
 private static final long serialVersionUID = 2341653211621224652L;
 boolean ts, ap, ek;
 int vk;

 public KeyboardEvent(Object source, boolean ts, int vk, boolean ap,
 boolean ek) {
 super (source);
 this .ts = ts;
 this .vk = vk;
 this .ap = ap;
 this .ek = ek;
 }

 public boolean getTransitionState() {
 return ts;
 }

 public long getVirtualKeyCode() {
 return vk;
 }

 public boolean isAltPressed() {
 return ap;
 }

 public boolean isExtendedKey() {
 return ek;
 }

 public boolean equals(KeyboardEvent event) {
 if (event.getVirtualKeyCode() == vk) {
 if (event.isExtendedKey() == ek) {
 if (event.isAltPressed() == ap) {
 return true ;
 }
 }
 }
 return false ;
 }
}

MouseEventListenter.java

import java.util.*;

public interface MouseEventListener extends EventListener {
 public void GlobalMouseX(MouseEvent event);

 public void GlobalMouseY(MouseEvent event);
}

class MouseEvent extends EventObject {

 private static final long serialVersionUID = 14654L;
 int cord_x, cord_y;

 public MouseEvent(Object source, int cord_x, int cord_y) {
 super (source);
 this .cord_x = cord_x;
 this .cord_y = cord_y;
 }

 public int getMouseX() {
 return cord_x;
 }

 public int getMouseY() {
 return cord_y;
 }

}

GlobalEventListener.java :

public class GlobalEventListener {
 PoolHook pt;

 public GlobalEventListener() {
 pt = new PoolHook( this );
 pt.start();

 }

 protected javax.swing.event.EventListenerList listenerList = new javax.swing.event.EventListenerList();

 public void addKeyboardEventListener(KeyboardEventListener listener) {
 listenerList.add(KeyboardEventListener. class , listener);
 }

 public void removeKeyboardEventListener(KeyboardEventListener listener) {
 listenerList.remove(KeyboardEventListener. class , listener);
 }

 public void addMouseEventListener(MouseEventListener listener) {
 listenerList.add(MouseEventListener. class , listener);
 }

 public void removeMouseEventListener(MouseEventListener listener) {
 listenerList.remove(MouseEventListener. class , listener);
 }

 void keyPressed(KeyboardEvent event) {
 Object[] listeners = listenerList.getListenerList();
 for ( int i = 0 ; i < listeners.length; i += 2 ) {
 if (listeners[i] == KeyboardEventListener. class ) {
 ((KeyboardEventListener) listeners[i + 1 ])
 .GlobalKeyPressed(event);
 }
 }
 }

 void mouseMoved(MouseEvent event) {
 Object[] listeners = listenerList.getListenerList();
 for ( int i = 0 ; i < listeners.length; i += 2 ) {
 if (listeners[i] == MouseEventListener. class ) {
 ((MouseEventListener) listeners[i + 1 ]).GlobalMouseX(event);
 ((MouseEventListener) listeners[i + 1 ]).GlobalMouseY(event);
 }
 }
 }

 void keyReleased(KeyboardEvent event) {
 Object[] listeners = listenerList.getListenerList();
 for ( int i = 0 ; i < listeners.length; i += 2 ) {
 if (listeners[i] == KeyboardEventListener. class ) {
 ((KeyboardEventListener) listeners[i + 1 ])
 .GlobalKeyReleased(event);
 }
 }
 }

}

SysHook.java:

class PoolHook extends Thread {
 SysHook hook;
 GlobalEventListener g_gl;

 PoolHook(GlobalEventListener gl) {
 g_gl = gl;
 }

 public void run() {
 hook = new SysHook();
 hook.registerHook(g_gl);
 }

}

class SysHook {

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

 void processKey( boolean ts, int vk, GlobalEventListener gl) {
 KeyboardEvent event = new KeyboardEvent( this , ts, vk, false , false );
 gl.keyPressed(event);
 }

 void mouseMoved( int cord_x, int cord_y, GlobalEventListener gl) {
 MouseEvent event = new MouseEvent( this , cord_x, cord_y);
 gl.mouseMoved(event);
 }

 native void registerHook(GlobalEventListener gl);

 native void unRegisterHook();

}

Example.java:

public class Example implements KeyboardEventListener, MouseEventListener {

 static GlobalEventListener gl;

 public static void main(String[] args) throws Exception {
 Example inst = new Example();
 gl = new GlobalEventListener();
 gl.addKeyboardEventListener(inst);
 gl.addMouseEventListener(inst);
 }

 @Override
 public void GlobalKeyPressed(KeyboardEvent event) {

 System.out.println( "Key Pressed: " + event.getVirtualKeyCode());
 }

 @Override
 public void GlobalKeyReleased(KeyboardEvent event) {
 }

 @Override
 public void GlobalMouseX(MouseEvent event) {
 System.out.println( "Mouse X: " + event.getMouseX());

 }

 @Override
 public void GlobalMouseY(MouseEvent event) {
 System.out.println( "Mouse Y: " + event.getMouseY());
 }

}

C++文件需要用Visual Studio编译为你的目标系统的DLL文件。如果是标准32位Windows XP，可以在这里下载已编译的文件。

在Eclipse创建工程后，需要做的设置是将该DLL所在目录添加到Native library location如图：

本文摘录、翻译并修改自http://www.jotschi.de/?p=90