package test11; 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 说明:文件加密 加密方法:三重DES加密 * 加密过程:对选中的文件加密后在同文件夹下生成一个增加了".tdes" 扩展名的加密文件 * * 解密过程:对选中的加密文件(必须有".tdes"扩展名)进行解密 */ 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() { //设置屏幕窗口大小 this.setSize(WIDTH, HEIGHT); this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //设置是否可以调节大小 this.setResizable(false); //设置窗口初始出现位置 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)"); //建立一个容器 Container c = this.getContentPane(); //设置布局 c.setLayout(new FlowLayout()); //容器中添加内容 final FilePanel fp = new FilePanel("文件选择:"); c.add(fp); final KeyPanel pp = new KeyPanel("密码:"); c.add(pp); JButton jbE = new JButton("加密"); c.add(jbE); //给加密按钮添加相应事件 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, "请选择文件!", "提示",JOptionPane.OK_OPTION); } }); //添加解密按钮,增加监听事件 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, "请选择文件!", "提示",JOptionPane.OK_OPTION); } }); } /** * 加密函数 输入: 要加密的文件,密码(由0-F组成,共48个字符,表示3个8位的密码)如: * AD67EA2F3BE6E5ADD368DFE03120B5DF92A8FD8FEC2F0746 其中: AD67EA2F3BE6E5AD * DES密码一 D368DFE03120B5DF DES密码二 92A8FD8FEC2F0746 DES密码三 输出: * 对输入的文件加密后,保存到同一文件夹下增加了".tdes"扩展名的文件中。 */ 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, "密码长度必须等于48!", "错误信息",JOptionPane.ERROR_MESSAGE); } catch (Exception e) { e.printStackTrace(); } } /** * 解密函数 输入: 要解密的文件,密码(由0-F组成,共48个字符,表示3个8位的密码)如: * AD67EA2F3BE6E5ADD368DFE03120B5DF92A8FD8FEC2F0746 其中: AD67EA2F3BE6E5AD * DES密码一 D368DFE03120B5DF DES密码二 92A8FD8FEC2F0746 DES密码三 输出: * 对输入的文件解密后,保存到用户指定的文件中。 */ 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)); // 用户指定要保存的文件 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, "密码长度必须等于48!", "错误信息",JOptionPane.ERROR_MESSAGE); } catch (Exception e) { JOptionPane.showMessageDialog(this, "解密失败,请核对密码!", "提示",JOptionPane.OK_OPTION); } } /** * 用DES方法加密输入的字节 bytKey需为8字节长,是加密的密码 */ 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方法解密输入的字节 bytKey需为8字节长,是解密的密码 */ 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); } /** * 输入密码的字符形式,返回字节数组形式。 如输入字符串:AD67EA2F3BE6E5AD 返回字节数组:{ * 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; } /** * 计算一个16进制字符的10进制值 输入: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; } } /** * 文件选择组件。 */ class FilePanel extends JPanel { FilePanel(String str) { JLabel label = new JLabel(str); JTextField fileText = new JTextField(35); JButton chooseButton = new JButton("浏览..."); 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; } } /** * 密码生成组件。 */ class KeyPanel extends JPanel { KeyPanel(String str) { JLabel label = new JLabel(str); JTextField fileText = new JTextField(35); JButton chooseButton = new JButton("随机产生"); this.add(label); this.add(fileText); this.add(chooseButton); clickAction ca = new clickAction(this); chooseButton.addActionListener(ca); } // 返回生成的密码(48个字符长度) 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); System.out.println(strRet); strRet += getHexValue(byt[i] & 15); System.out.println(strRet); } 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; } }
下边是一个小的数据加密例子,可以实现简单的文本加密:
package test11; import java.lang.reflect.Method; import javax.crypto.Cipher; import javax.crypto.SecretKey; import javax.crypto.SecretKeyFactory; import javax.crypto.spec.DESKeySpec; public class TestMi { //单例模式 private TestMi nn; public TestMi getTestMi(){ if(nn == null){ this.nn = new TestMi(); } return nn; } public static void main(String[] args) throws Exception { String str = new TestMi().encryption("张三", "12345678", "encryptByDES"); System.out.println(str); String str1 = new TestMi().encryption(str, "12345678", "decryptByDES"); System.out.println(str1); } public String encryption(String str,String psw,String methodName) throws Exception{ Method m = getTestMi().getClass().getMethod(methodName,new Class[]{String.class,String.class}); String newStr = null; if(m != null){ newStr = (String) m.invoke(nn, str,psw); } return newStr; } /** * 用DES方法加密输入的字节 bytKey需为8字节长,是加密的密码 */ public String encryptByDES(String str1, String str2) throws Exception { byte[] bytP = str1.getBytes("UTF-8"); byte[] bytKey = str2.getBytes("UTF-8"); 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 new String(cip.doFinal(bytP),"ISO-8859-1"); } /** * 用DES方法解密输入的字节 bytKey需为8字节长,是解密的密码 */ public String decryptByDES(String str1, String str2) throws Exception { byte[] bytE = str1.getBytes("ISO-8859-1"); byte[] bytKey = str2.getBytes("ISO-8859-1"); 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 new String(cip.doFinal(bytE),"UTF-8"); } }