java文件加密

哈哈!不會是老師留給你的作業吧!在網上做牛!
VERSION 4.00
Begin VB.Form Form1
Caption = "Sample"
ClientHeight = 705
ClientLeft = 3915
ClientTop = 3315
ClientWidth = 1800
ControlBox = 0 'False
Height = 1110
Left = 3855
LinkTopic = "Form1"
MaxButton = 0 'False
MinButton = 0 'False
ScaleHeight = 705
ScaleWidth = 1800
Top = 2970
Width = 1920
Begin VB.CommandButton Command1
Caption = "Command1"
Height = 495
Left = 240
TabIndex = 0
Top = 120
Width = 1215
End
End
Attribute VB_Name = "Form1"
Attribute VB_Creatable = False
Attribute VB_Exposed = False
Sub FileEncodeAndDecode(InputFile As String, OutputFile As String, PasswordKey As String)

Dim temp As Single
Dim Char As String * 1
Dim XORMask As Single
Dim temp1 As Integer

Open InputFile For Binary As #1
Open OutputFile For Binary As #2

For x = 1 To Len(PasswordKey)
temp = Asc(Mid$(PasswordKey, x, 1))
For y = 1 To temp
temp1 = Rnd
Next y

' Re-seed to throw off prying eyes
Randomize temp1
Next x

Counter = 0
For z = 1 To FileLen(InputFile)

'Generate random mask
XORMask = Int(Rnd * 256)

'Get the char & change it
Get 1, , Char
Char = Chr$((Asc(Char) Xor XORMask))
Put 2, , Char

Counter = Counter + 1
If Counter > Len(PasswordKey) Then Counter = 1

' Pull random numbers from the hat
For x = 1 To (Asc(Mid$(PasswordKey, Counter, 1)) * 2)
temp = Rnd
Next x
Next z

Close #1
Close #2

End Sub

Private Sub Command1_Click()

Dim InputFile As String
Dim OutputFile As String
Dim PasswordKey As String

InputFile = InputBox("Enter a filename to encode")
OutputFile = InputBox("Enter the new filename this will become ")
PasswordKey = InputBox("Enter the password (key)")

Call FileEncodeAndDecode(InputFile, OutputFile, PasswordKey)

MsgBox "File written to " + OutputFile
End
End Sub

Private Sub Form_Load()

Command1.Caption = "Code/Decode"

End Sub

Form=enc-dec.frm
Reference=*\G{BEF6E001-A874-101A-8BBA-00AA00300CAB}#2.0#0#D:\WINDOWS\SYSTEM\OLEPRO32.DLL#Standard OLE Types
Reference=*\G{00025E01-0000-0000-C000-000000000046}#3.0#0#D:\PROGRAM FILES\COMMON FILES\MICROSOFT SHARED\DD:\PROGRAM FIL#Microsoft DAO 3.0 Object Library
ProjWinSize=113,438,221,107
ProjWinShow=2
Name="Project1"
HelpContextID="0"
StartMode=0
VersionCompatible32="0"
MajorVer=1
MinorVer=0
RevisionVer=0
AutoIncrementVer=0
ServerSupportFiles=0
VersionCompanyName="Southern Cross Software"

⑵ 用JAVA對文件進行加密的方法有幾種

以上不是文件進行加密,而是對密碼進行加密,對文件加密的話,去看看thingk in java 里有一章是說這個的

⑶ 如何利用JAVA對文檔進行加密和解密處理,完整的java類

import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.KeyPair;
import java.security.KeyPairGenerator;
import java.security.NoSuchAlgorithmException;
import java.security.interfaces.RSAPrivateKey;
import java.security.interfaces.RSAPublicKey;
import javax.crypto.Cipher;

public class RSAEncrypt {

static KeyPairGenerator keyPairGen;

static KeyPair keyPair;

static RSAPrivateKey privateKey;

static RSAPublicKey publicKey;

static{
{
keyPairGen = KeyPairGenerator.getInstance("RSA");
keyPairGen.initialize(512);
keyPair = keyPairGen.generateKeyPair();
// Generate keys
privateKey = (RSAPrivateKey) keyPair.getPrivate();
publicKey = (RSAPublicKey) keyPair.getPublic();
} catch (NoSuchAlgorithmException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}

public static void main(String[] args) {
RSAEncrypt encrypt = new RSAEncrypt();
File file = new File(
"C:\\Documents and Settings\\Administrator.DCB5E0D91E0D436\\桌面\\sdf.txt");
File newFile = new File(
"C:\\Documents and Settings\\Administrator.DCB5E0D91E0D436\\桌面\\sdf1.txt");
encrypt.encryptFile(encrypt, file, newFile);
File file1 = new File(
"C:\\Documents and Settings\\Administrator.DCB5E0D91E0D436\\桌面\\sdf1.txt");
File newFile1 = new File(
"C:\\Documents and Settings\\Administrator.DCB5E0D91E0D436\\桌面\\sdf2.txt");
encrypt.decryptFile(encrypt, file1, newFile1);
}

public void encryptFile(RSAEncrypt encrypt, File file, File newFile) {
try {
InputStream is = new FileInputStream(file);
OutputStream os = new FileOutputStream(newFile);

byte[] bytes = new byte[53];
while (is.read(bytes) > 0) {
byte[] e = encrypt.encrypt(RSAEncrypt.publicKey, bytes);
bytes = new byte[53];
os.write(e, 0, e.length);
}
os.close();
is.close();
System.out.println("write success");
} catch (Exception e) {
e.printStackTrace();
}
}

public void decryptFile(RSAEncrypt encrypt, File file, File newFile) {
try {
InputStream is = new FileInputStream(file);
OutputStream os = new FileOutputStream(newFile);
byte[] bytes1 = new byte[64];
while (is.read(bytes1) > 0) {
byte[] de = encrypt.decrypt(RSAEncrypt.privateKey, bytes1);
bytes1 = new byte[64];
os.write(de, 0, de.length);
}
os.close();
is.close();
System.out.println("write success");

} catch (Exception e) {
e.printStackTrace();
}
}

/** */
/**
* * Encrypt String. *
*
* @return byte[]
*/
protected byte[] encrypt(RSAPublicKey publicKey, byte[] obj) {
if (publicKey != null) {
try {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.ENCRYPT_MODE, publicKey);
return cipher.doFinal(obj);
} catch (Exception e) {
e.printStackTrace();
}
}
return null;
}

/** */
/**
* * Basic decrypt method *
*
* @return byte[]
*/
protected byte[] decrypt(RSAPrivateKey privateKey, byte[] obj) {
if (privateKey != null) {
try {
Cipher cipher = Cipher.getInstance("RSA");
cipher.init(Cipher.DECRYPT_MODE, privateKey);
return cipher.doFinal(obj);
} catch (Exception e) {
e.printStackTrace();
}
}
return null;
}
}

加解密需要依靠以下四個屬性,你可以把它存文件,存資料庫都無所謂:
static KeyPairGenerator keyPairGen;

static KeyPair keyPair;

static RSAPrivateKey privateKey;

static RSAPublicKey publicKey;

以上只是示例,怎麼存放根據自己情況

⑷ java 對文件逐位元組加密

fis應該可以轉化為byet[]吧 這樣應該可以逐位元組加密了...
你真的要讓加密文件包含 內容 + 密鑰 + 加密算嗎嗎? 那byte[] 可以append一下就加上了,,,,

⑸ java用io怎麼對文件進行加密代碼!!

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;

/**
文件名:FileEncrypter.java
JDK:1.40以上
說明:文件加密
加密方法:三重DES加密
加密過程:對選中的文件加密後在同文件夾下生成一個增加了".tdes"
擴展名的加密文件
解密過程:對選中的加密文件(必須有".tdes"擴展名)進行解密
*/
public class FileEncrypter extends JFrame{
public static final int WIDTH = 550;
public static final int HEIGHT = 200;

public static void main(String args[]) {
FileEncrypter fe = new FileEncrypter();
fe.show();
}

FileEncrypter(){
this.setSize(WIDTH,HEIGHT);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setResizable(false);
Toolkit tk = Toolkit.getDefaultToolkit();
Dimension screenSize = tk.getScreenSize();
this.setLocation((screenSize.width - WIDTH)/2,
(screenSize.height - HEIGHT)/2);
this.setTitle("文件加密器(TriDES)");
Container c = this.getContentPane();
c.setLayout( new FlowLayout());

final FilePanel fp = new FilePanel("文件選擇");
c.add(fp);

final KeyPanel pp = new KeyPanel("密碼");
c.add(pp);

JButton jbE = new JButton("加密");
c.add(jbE);
jbE.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event){
File file = new File(fp.getFileName());
if (file.exists())
encrypt(file.getAbsoluteFile(),pp.getKey());
else
JOptionPane.showMessageDialog(
null,"請選擇文件!","提示",JOptionPane.OK_OPTION);
}
});
JButton jbD = new JButton("解密");
c.add(jbD);
jbD.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event){
File file = new File(fp.getFileName());
if (file.exists())
decrypt(file.getAbsoluteFile(),pp.getKey());
else
JOptionPane.showMessageDialog(
null,"請選擇文件!","提示",JOptionPane.OK_OPTION);
}
});
}

/**
加密函數
輸入:
要加密的文件,密碼(由0-F組成,共48個字元,表示3個8位的密碼)如:

其中:
AD67EA2F3BE6E5AD DES密碼一
D368DFE03120B5DF DES密碼二
92A8FD8FEC2F0746 DES密碼三
輸出:
對輸入的文件加密後,保存到同一文件夾下增加了".tdes"擴展名的文件中。
*/
private void encrypt(File fileIn,String sKey){
try{
if(sKey.length() == 48){
byte[] bytK1 = getKeyByStr(sKey.substring(0,16));
byte[] bytK2 = getKeyByStr(sKey.substring(16,32));
byte[] bytK3 = getKeyByStr(sKey.substring(32,48));

FileInputStream fis = new FileInputStream(fileIn);
byte[] bytIn = new byte[(int)fileIn.length()];
for(int i = 0;i<FILEIN.LENGTH();I++){
bytIn[i] = (byte)fis.read();
}
//加密
byte[] bytOut = encryptByDES(encryptByDES(
encryptByDES(bytIn,bytK1),bytK2),bytK3);
String fileOut = fileIn.getPath() + ".tdes";
FileOutputStream fos = new FileOutputStream(fileOut);
for(int i = 0;i<BYTOUT.LENGTH;I++){
fos.write((int)bytOut[i]);
}
fos.close();
JOptionPane.showMessageDialog(
this,"加密成功!","提示",JOptionPane.OK_OPTION);
}else
JOptionPane.showMessageDialog(
this,"密碼長度必須等於48!","錯誤信息",JOptionPane.ERROR_MESSAGE);
}catch(Exception e){
e.printStackTrace();
}
}

/**
解密函數
輸入:
要解密的文件,密碼(由0-F組成,共48個字元,表示3個8位的密碼)如:

其中:
AD67EA2F3BE6E5AD DES密碼一
D368DFE03120B5DF DES密碼二
92A8FD8FEC2F0746 DES密碼三
輸出:
對輸入的文件解密後,保存到用戶指定的文件中。
*/
private void decrypt(File fileIn,String sKey){
try{
if(sKey.length() == 48){
String strPath = fileIn.getPath();
if(strPath.substring(strPath.length()-5).toLowerCase().equals(".tdes"))
strPath = strPath.substring(0,strPath.length()-5);
else{
JOptionPane.showMessageDialog(
this,"不是合法的加密文件!","提示",JOptionPane.OK_OPTION);
return;
}
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
chooser.setSelectedFile(new File(strPath));
//用戶指定要保存的文件
int ret = chooser.showSaveDialog(this);
if(ret==JFileChooser.APPROVE_OPTION){

byte[] bytK1 = getKeyByStr(sKey.substring(0,16));
byte[] bytK2 = getKeyByStr(sKey.substring(16,32));
byte[] bytK3 = getKeyByStr(sKey.substring(32,48));

FileInputStream fis = new FileInputStream(fileIn);
byte[] bytIn = new byte[(int)fileIn.length()];
for(int i = 0;i<FILEIN.LENGTH();I++){
bytIn[i] = (byte)fis.read();
}
//解密
byte[] bytOut = decryptByDES(decryptByDES(
decryptByDES(bytIn,bytK3),bytK2),bytK1);
File fileOut = chooser.getSelectedFile();
fileOut.createNewFile();
FileOutputStream fos = new FileOutputStream(fileOut);
for(int i = 0;i<BYTOUT.LENGTH;I++){
fos.write((int)bytOut[i]);
}
fos.close();
JOptionPane.showMessageDialog(
this,"解密成功!","提示",JOptionPane.OK_OPTION);
}
}else
JOptionPane.showMessageDialog(
this,"密碼長度必須等於48!","錯誤信息",JOptionPane.ERROR_MESSAGE);
}catch(Exception e){
JOptionPane.showMessageDialog(
this,"解密失敗,請核對密碼!","提示",JOptionPane.OK_OPTION);
}
}

/**
用DES方法加密輸入的位元組
bytKey需為8位元組長,是加密的密碼
*/
private byte[] encryptByDES(byte[] bytP,byte[] bytKey) throws Exception{
DESKeySpec desKS = new DESKeySpec(bytKey);
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey sk = skf.generateSecret(desKS);
Cipher cip = Cipher.getInstance("DES");
cip.init(Cipher.ENCRYPT_MODE,sk);
return cip.doFinal(bytP);
}

/**
用DES方法解密輸入的位元組
bytKey需為8位元組長,是解密的密碼
*/
private byte[] decryptByDES(byte[] bytE,byte[] bytKey) throws Exception{
DESKeySpec desKS = new DESKeySpec(bytKey);
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey sk = skf.generateSecret(desKS);
Cipher cip = Cipher.getInstance("DES");
cip.init(Cipher.DECRYPT_MODE,sk);
return cip.doFinal(bytE);
}

/**
輸入密碼的字元形式,返回位元組數組形式。
如輸入字元串:AD67EA2F3BE6E5AD
返回位元組數組:{173,103,234,47,59,230,229,173}
*/
private byte[] getKeyByStr(String str){
byte[] bRet = new byte[str.length()/2];
for(int i=0;i<STR.LENGTH()
Integer itg =
new Integer(16*getChrInt(str.charAt(2*i)) + getChrInt(str.charAt(2*i+1)));
bRet[i] = itg.byteValue();
}
return bRet;
}
/**
計算一個16進制字元的10進制值
輸入:0-F
*/
private int getChrInt(char chr){
int iRet=0;
if(chr=="0".charAt(0)) iRet = 0;
if(chr=="1".charAt(0)) iRet = 1;
if(chr=="2".charAt(0)) iRet = 2;
if(chr=="3".charAt(0)) iRet = 3;
if(chr=="4".charAt(0)) iRet = 4;
if(chr=="5".charAt(0)) iRet = 5;
if(chr=="6".charAt(0)) iRet = 6;
if(chr=="7".charAt(0)) iRet = 7;
if(chr=="8".charAt(0)) iRet = 8;
if(chr=="9".charAt(0)) iRet = 9;
if(chr=="A".charAt(0)) iRet = 10;
if(chr=="B".charAt(0)) iRet = 11;
if(chr=="C".charAt(0)) iRet = 12;
if(chr=="D".charAt(0)) iRet = 13;
if(chr=="E".charAt(0)) iRet = 14;
if(chr=="F".charAt(0)) iRet = 15;
return iRet;
}
}

/**
文件選擇組件。
*/
class FilePanel extends JPanel{
FilePanel(String str){
JLabel label = new JLabel(str);
JTextField fileText = new JTextField(35);
JButton chooseButton = new JButton("瀏覽...");
this.add(label);
this.add(fileText);
this.add(chooseButton);
clickAction ca = new clickAction(this);
chooseButton.addActionListener(ca);

}

public String getFileName(){
JTextField jtf = (JTextField)this.getComponent(1);
return jtf.getText();
}

private class clickAction implements ActionListener{
clickAction(Component c){
cmpt = c;
}

public void actionPerformed(ActionEvent event){
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
int ret = chooser.showOpenDialog(cmpt);
if(ret==JFileChooser.APPROVE_OPTION){
JPanel jp = (JPanel)cmpt;
JTextField jtf = (JTextField)jp.getComponent(1);
jtf.setText(chooser.getSelectedFile().getPath());
}
}

private Component cmpt;
}
}

/**
密碼生成組件。
*/
class KeyPanel extends JPanel{
KeyPanel(String str){
JLabel label = new JLabel(str);
JTextField fileText = new JTextField(35);
JButton chooseButton = new JButton("隨機產生");
this.add(label);
this.add(fileText);
this.add(chooseButton);
clickAction ca = new clickAction(this);
chooseButton.addActionListener(ca);

}

//返回生成的密碼(48個字元長度)
public String getKey(){
JTextField jtf = (JTextField)this.getComponent(1);
return jtf.getText();
}

private class clickAction implements ActionListener{
clickAction(Component c){
cmpt = c;
}

public void actionPerformed(ActionEvent event){
try{
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(56);
Key ke = kg.generateKey();
byte[] bytK1 = ke.getEncoded();
ke = kg.generateKey();
byte[] bytK2 = ke.getEncoded();
ke = kg.generateKey();
byte[] bytK3 = ke.getEncoded();

JPanel jp = (JPanel)cmpt;
JTextField jtf = (JTextField)jp.getComponent(1);
jtf.setText(getByteStr(bytK1)+getByteStr(bytK2)+getByteStr(bytK3));
}catch(Exception e){
e.printStackTrace();
}
}

private String getByteStr(byte[] byt){
String strRet = "";
for(int i=0;i<BYT.LENGTH;I++){
//System.out.println(byt[i]);
strRet += getHexValue((byt[i]&240)/16);
strRet += getHexValue(byt[i]&15);
}
return strRet;
}

private String getHexValue(int s){
String sRet=null;
switch (s){
case 0: sRet = "0";break;
case 1: sRet = "1";break;
case 2: sRet = "2";break;
case 3: sRet = "3";break;
case 4: sRet = "4";break;
case 5: sRet = "5";break;
case 6: sRet = "6";break;
case 7: sRet = "7";break;
case 8: sRet = "8";break;
case 9: sRet = "9";break;
case 10: sRet = "A";break;
case 11: sRet = "B";break;
case 12: sRet = "C";break;
case 13: sRet = "D";break;
case 14: sRet = "E";break;
case 15: sRet = "F";
}
return sRet;
}

private Component cmpt;
}
}

⑹ 怎麼用java給文件夾加密

去看看java.security,javax.crypto這兩包里的類吧,裡面有加密的演算法,其中有一個流加密就是爭對文件內容的。
本來想把代碼給你看看的,不過那樣你就不做事了,給你兩包,上網去查查這兩包里的類做什麼的,說不準你會得到更多關於這方面的信息,到時你要謝謝我,哈。。。。

⑺ java中如何實現對文件和字元串加密. 解密

你好,加密的方式有很多中,如傳統加密,後期的分組加密,序列流加密,這內些是對稱加容密,現在有著名的非對稱加密。
java的擴展包很好的實現了你需要的功能。這個包在java.security.*;當然了還有很多好的加密方法,在sun的第三方jar包中有。目前密碼加密使用用的是MD5加密,這個是單向加密,不可以解密。要想實現加密和解密,那麼就需要學習密碼學的知識。
希望對你有所幫助。

⑻ java 一個將文件加密的程序

import java.io.*;

class Encrypt{
private String pw;
private File fin;
private File fout;
public Encrypt(File fin,String pw,File fout) throws Exception{
if("".equals(pw)){
System.out.println("密碼不能為空");
System.exit(1);
}
this.pw=pw;
if(!fin.exists()){
System.out.println("輸入文件不存在");
System.exit(1);
}
this.fin=fin;
if(fout.exists()){
System.out.println("輸出文件已存在");
System.exit(1);
}
this.fout=fout;
this.enc();
}

public void enc() throws Exception{
byte[] pass=pw.getBytes();
int length=pw.length();
int i=0;
InputStream in=new FileInputStream(fin);
OutputStream out=new FileOutputStream(fout);
int indata;
indata=in.read();
while(indata!=-1){
i++;
indata^=pass[i%length];
out.write(indata);
System.out.print((char)indata);
indata=in.read();
}
in.close();
out.close();

}
}
public class EncryptFile{
public static void main(String args[]) throws Exception{
if(args.length!=3){
System.out.println("參數錯誤:參數格式應為: input_file password output_file");
System.exit(1);
}
File fin=new File(args[0]);
File fout=new File(args[2]);
new Encrypt(fin,args[1],fout);
}
}

沒完全按照你的要求 自己再改改吧 ~~~~~~~~~

⑼ 怎樣用JAVA給文件夾加密,拜求各位大俠!

一個例子
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.io.*;
import java.security.*;
import javax.crypto.*;
import javax.crypto.spec.*;

/**
文件名:FileEncrypter.java
JDK:1.40以上
說明:文件加密
加密方法:三重DES加密
加密過程:對選中的文件加密後在同文件夾下生成一個增加了".tdes"
擴展名的加密文件

解密過程:對選中的加密文件(必須有".tdes"擴展名)進行解密
*/
public class FileEncrypter extends JFrame{
public static final int WIDTH = 550;
public static final int HEIGHT = 200;

public static void main(String args[]) {
FileEncrypter fe = new FileEncrypter();
fe.show();
}

FileEncrypter(){
this.setSize(WIDTH,HEIGHT);
this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
this.setResizable(false);
Toolkit tk = Toolkit.getDefaultToolkit();
Dimension screenSize = tk.getScreenSize();
this.setLocation((screenSize.width - WIDTH)/2,
(screenSize.height - HEIGHT)/2);
this.setTitle("文件加密器(TriDES)");
Container c = this.getContentPane();
c.setLayout( new FlowLayout());

final FilePanel fp = new FilePanel("文件選擇");
c.add(fp);

final KeyPanel pp = new KeyPanel("密碼");
c.add(pp);

JButton jbE = new JButton("加密");
c.add(jbE);
jbE.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event){
File file = new File(fp.getFileName());
if (file.exists())
encrypt(file.getAbsoluteFile(),pp.getKey());
else
JOptionPane.showMessageDialog(
null,"請選擇文件!","提示",JOptionPane.OK_OPTION);
}
});
JButton jbD = new JButton("解密");
c.add(jbD);
jbD.addActionListener(new ActionListener(){
public void actionPerformed(ActionEvent event){
File file = new File(fp.getFileName());
if (file.exists())
decrypt(file.getAbsoluteFile(),pp.getKey());
else
JOptionPane.showMessageDialog(
null,"請選擇文件!","提示",JOptionPane.OK_OPTION);
}
});
}

/**
加密函數
輸入:
要加密的文件,密碼(由0-F組成,共48個字元,表示3個8位的密碼)如:

其中:
AD67EA2F3BE6E5AD DES密碼一
D368DFE03120B5DF DES密碼二
92A8FD8FEC2F0746 DES密碼三
輸出:
對輸入的文件加密後,保存到同一文件夾下增加了".tdes"擴展名的文件中。
*/
private void encrypt(File fileIn,String sKey){
try{
if(sKey.length() == 48){
byte[] bytK1 = getKeyByStr(sKey.substring(0,16));
byte[] bytK2 = getKeyByStr(sKey.substring(16,32));
byte[] bytK3 = getKeyByStr(sKey.substring(32,48));

FileInputStream fis = new FileInputStream(fileIn);
byte[] bytIn = new byte[(int)fileIn.length()];
for(int i = 0;i<fileIn.length();i++){
bytIn[i] = (byte)fis.read();
}
//加密
byte[] bytOut = encryptByDES(encryptByDES(
encryptByDES(bytIn,bytK1),bytK2),bytK3);
String fileOut = fileIn.getPath() + ".tdes";
FileOutputStream fos = new FileOutputStream(fileOut);
for(int i = 0;i<bytOut.length;i++){
fos.write((int)bytOut[i]);
}
fos.close();
JOptionPane.showMessageDialog(
this,"加密成功!","提示",JOptionPane.OK_OPTION);
}else
JOptionPane.showMessageDialog(
this,"密碼長度必須等於48!","錯誤信息",JOptionPane.ERROR_MESSAGE);
}catch(Exception e){
e.printStackTrace();
}
}

/**
解密函數
輸入:
要解密的文件,密碼(由0-F組成,共48個字元,表示3個8位的密碼)如:

其中:
AD67EA2F3BE6E5AD DES密碼一
D368DFE03120B5DF DES密碼二
92A8FD8FEC2F0746 DES密碼三
輸出:
對輸入的文件解密後,保存到用戶指定的文件中。
*/
private void decrypt(File fileIn,String sKey){
try{
if(sKey.length() == 48){
String strPath = fileIn.getPath();
if(strPath.substring(strPath.length()-5).toLowerCase().equals(".tdes"))
strPath = strPath.substring(0,strPath.length()-5);
else{
JOptionPane.showMessageDialog(
this,"不是合法的加密文件!","提示",JOptionPane.OK_OPTION);
return;
}
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
chooser.setSelectedFile(new File(strPath));
//用戶指定要保存的文件
int ret = chooser.showSaveDialog(this);
if(ret==JFileChooser.APPROVE_OPTION){

byte[] bytK1 = getKeyByStr(sKey.substring(0,16));
byte[] bytK2 = getKeyByStr(sKey.substring(16,32));
byte[] bytK3 = getKeyByStr(sKey.substring(32,48));

FileInputStream fis = new FileInputStream(fileIn);
byte[] bytIn = new byte[(int)fileIn.length()];
for(int i = 0;i<fileIn.length();i++){
bytIn[i] = (byte)fis.read();
}
//解密
byte[] bytOut = decryptByDES(decryptByDES(
decryptByDES(bytIn,bytK3),bytK2),bytK1);
File fileOut = chooser.getSelectedFile();
fileOut.createNewFile();
FileOutputStream fos = new FileOutputStream(fileOut);
for(int i = 0;i<bytOut.length;i++){
fos.write((int)bytOut[i]);
}
fos.close();
JOptionPane.showMessageDialog(
this,"解密成功!","提示",JOptionPane.OK_OPTION);
}
}else
JOptionPane.showMessageDialog(
this,"密碼長度必須等於48!","錯誤信息",JOptionPane.ERROR_MESSAGE);
}catch(Exception e){
JOptionPane.showMessageDialog(
this,"解密失敗,請核對密碼!","提示",JOptionPane.OK_OPTION);
}
}

/**
用DES方法加密輸入的位元組
bytKey需為8位元組長,是加密的密碼
*/
private byte[] encryptByDES(byte[] bytP,byte[] bytKey) throws Exception{
DESKeySpec desKS = new DESKeySpec(bytKey);
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey sk = skf.generateSecret(desKS);
Cipher cip = Cipher.getInstance("DES");
cip.init(Cipher.ENCRYPT_MODE,sk);
return cip.doFinal(bytP);
}

/**
用DES方法解密輸入的位元組
bytKey需為8位元組長,是解密的密碼
*/
private byte[] decryptByDES(byte[] bytE,byte[] bytKey) throws Exception{
DESKeySpec desKS = new DESKeySpec(bytKey);
SecretKeyFactory skf = SecretKeyFactory.getInstance("DES");
SecretKey sk = skf.generateSecret(desKS);
Cipher cip = Cipher.getInstance("DES");
cip.init(Cipher.DECRYPT_MODE,sk);
return cip.doFinal(bytE);
}

/**
輸入密碼的字元形式,返回位元組數組形式。
如輸入字元串:AD67EA2F3BE6E5AD
返回位元組數組:{ 173,103,234,47,59,230,229,173 }
*/
private byte[] getKeyByStr(String str){
byte[] bRet = new byte[str.length()/2];
for(int i=0;i<str.length()/2;i++){
Integer itg =
new Integer(16*getChrInt(str.charAt(2*i)) + getChrInt(str.charAt(2*i+1)));
bRet[i] = itg.byteValue();
}
return bRet;
}
/**
計算一個16進制字元的10進制值
輸入:0-F
*/
private int getChrInt(char chr){
int iRet=0;
if(chr=="0".charAt(0)) iRet = 0;
if(chr=="1".charAt(0)) iRet = 1;
if(chr=="2".charAt(0)) iRet = 2;
if(chr=="3".charAt(0)) iRet = 3;
if(chr=="4".charAt(0)) iRet = 4;
if(chr=="5".charAt(0)) iRet = 5;
if(chr=="6".charAt(0)) iRet = 6;
if(chr=="7".charAt(0)) iRet = 7;
if(chr=="8".charAt(0)) iRet = 8;
if(chr=="9".charAt(0)) iRet = 9;
if(chr=="A".charAt(0)) iRet = 10;
if(chr=="B".charAt(0)) iRet = 11;
if(chr=="C".charAt(0)) iRet = 12;
if(chr=="D".charAt(0)) iRet = 13;
if(chr=="E".charAt(0)) iRet = 14;
if(chr=="F".charAt(0)) iRet = 15;
return iRet;
}
}

/**
文件選擇組件。
*/
class FilePanel extends JPanel{
FilePanel(String str){
JLabel label = new JLabel(str);
JTextField fileText = new JTextField(35);
JButton chooseButton = new JButton("瀏覽...");
this.add(label);
this.add(fileText);
this.add(chooseButton);
clickAction ca = new clickAction(this);
chooseButton.addActionListener(ca);

}

public String getFileName(){
JTextField jtf = (JTextField)this.getComponent(1);
return jtf.getText();
}

private class clickAction implements ActionListener{
clickAction(Component c){
cmpt = c;
}

public void actionPerformed(ActionEvent event){
JFileChooser chooser = new JFileChooser();
chooser.setCurrentDirectory(new File("."));
int ret = chooser.showOpenDialog(cmpt);
if(ret==JFileChooser.APPROVE_OPTION){
JPanel jp = (JPanel)cmpt;
JTextField jtf = (JTextField)jp.getComponent(1);
jtf.setText(chooser.getSelectedFile().getPath());
}
}

private Component cmpt;
}
}

/**
密碼生成組件。
*/
class KeyPanel extends JPanel{
KeyPanel(String str){
JLabel label = new JLabel(str);
JTextField fileText = new JTextField(35);
JButton chooseButton = new JButton("隨機產生");
this.add(label);
this.add(fileText);
this.add(chooseButton);
clickAction ca = new clickAction(this);
chooseButton.addActionListener(ca);

}

//返回生成的密碼(48個字元長度)
public String getKey(){
JTextField jtf = (JTextField)this.getComponent(1);
return jtf.getText();
}

private class clickAction implements ActionListener{
clickAction(Component c){
cmpt = c;
}

public void actionPerformed(ActionEvent event){
try{
KeyGenerator kg = KeyGenerator.getInstance("DES");
kg.init(56);
Key ke = kg.generateKey();
byte[] bytK1 = ke.getEncoded();
ke = kg.generateKey();
byte[] bytK2 = ke.getEncoded();
ke = kg.generateKey();
byte[] bytK3 = ke.getEncoded();

JPanel jp = (JPanel)cmpt;
JTextField jtf = (JTextField)jp.getComponent(1);
jtf.setText(getByteStr(bytK1)+getByteStr(bytK2)+getByteStr(bytK3));
}catch(Exception e){
e.printStackTrace();
}
}

private String getByteStr(byte[] byt){
String strRet = "";
for(int i=0;i<byt.length;i++){
//System.out.println(byt[i]);
strRet += getHexValue((byt[i]&240)/16);
strRet += getHexValue(byt[i]&15);
}
return strRet;
}

private String getHexValue(int s){
String sRet=null;
switch (s){
case 0: sRet = "0";break;
case 1: sRet = "1";break;
case 2: sRet = "2";break;
case 3: sRet = "3";break;
case 4: sRet = "4";break;
case 5: sRet = "5";break;
case 6: sRet = "6";break;
case 7: sRet = "7";break;
case 8: sRet = "8";break;
case 9: sRet = "9";break;
case 10: sRet = "A";break;
case 11: sRet = "B";break;
case 12: sRet = "C";break;
case 13: sRet = "D";break;
case 14: sRet = "E";break;
case 15: sRet = "F";
}
return sRet;
}

private Component cmpt;
}
}