輸入輸出檔案加密

 package net.itdos.secrit;

import java.io.ByteArrayOutputStream;

import java.io.FileInputStream;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.io.ObjectInputStream;

import java.io.ObjectOutputStream;

import java.io.OutputStream;

import java.security.Key;

import javax.crypto.Cipher;

import javax.crypto.KeyGenerator;

import javax.crypto.SecretKey;

public class Jiajie {

/**

* @param args

*/

public static void main(String[] args) {

jiami();

jiemi();

}

private static void jiami() {

try {

//執行個體個 加密對象

Cipher cipher=Cipher.getInstance("AES");

// 執行個體密鑰

SecretKey secreKey = KeyGenerator.getInstance("AES").generateKey();

//通過secreKey加密

cipher.init(Cipher.ENCRYPT_MODE, secreKey);

byte[] result = cipher.doFinal("itdoselt444".getBytes());

//把key儲存到硬碟

FileOutputStream foskey = new FileOutputStream("txx_key");

ObjectOutputStream oossecreKey = new ObjectOutputStream(foskey);

oossecreKey.writeObject(secreKey);

oossecreKey.close();

foskey.close();

//把result儲存到硬碟

FileOutputStream fosresult = new FileOutputStream("txx_data");

fosresult.write(result);

fosresult.close();

System.out.println("end");

} catch (Exception e) {

e.printStackTrace();

private static void jiemi(){

FileInputStream fiskey = new FileInputStream("txx_key");

ObjectInputStream oiskey = new ObjectInputStream(fiskey);

Key key = (Key)oiskey.readObject();

oiskey.close();

fiskey.close();

//通過secreKey解密

cipher.init(Cipher.DECRYPT_MODE, key);

FileInputStream fisresult = new FileInputStream("txx_data");

ByteArrayOutputStream baos = new ByteArrayOutputStream();

copyStream(fisresult,baos);

byte[] result = cipher.doFinal(baos.toByteArray());

baos.close();

fisresult.close();

System.out.println(

new String(result));

private static void copyStream(InputStream fis,OutputStream fos){

byte[] buf = new byte[1024];

int len = fis.read(buf);

while (len != -1) {

fos.write(buf, 0, len);

len = fis.read(buf);

} catch (IOException e) {

// TODO Auto-generated catch block