Java加密算法Triple DES详解编程语言

import javax.crypto.Cipher;   
import javax.crypto.KeyGenerator;   
import javax.crypto.SecretKey;   
import javax.crypto.SecretKeyFactory;   
import javax.crypto.spec.DESedeKeySpec;   
import javax.crypto.spec.IvParameterSpec;   
   
/**  
 * 三重加密 3DES也作 Triple DES,  
 *   
 * @author stone  
 * @date 2014-03-10 02:14:37  
 */   
public class TripleDES {   
    // 算法名称   
    public static final String KEY_ALGORITHM = "DESede";   
    // 算法名称/加密模式/填充方式   
    public static final String CIPHER_ALGORITHM_ECB = "DESede/ECB/PKCS5Padding";   
    public static final String CIPHER_ALGORITHM_CBC = "DESede/CBC/PKCS5Padding";   
       
    private KeyGenerator keyGen;   
    private SecretKey secretKey;   
    private SecretKey secretKey2;   
    private Cipher cipher;   
    private static byte[] encryptData;   
       
    public static void main(String[] args) throws Exception {   
        TripleDES tripleDES = new TripleDES("ECB");   
        tripleDES.encrypt("sau8jzxlcvm,'123`98(*^&%^^JCB ZX>>A<S<}}{");   
        System.out.println("加密后：" + new String(encryptData));   
        System.out.println("解密后："+ new String(tripleDES.decrypt(encryptData)));   
           
        tripleDES = new TripleDES("CBC");   
        tripleDES.encrypt2("sau8jzxlc DQV#><«|vm,'123`98(*^&%^^JCB ZX>>A<S<}}{");   
        System.out.println("加密后：" + new String(encryptData));   
        System.out.println("解密后："+ new String(tripleDES.decrypt2(encryptData)));   
    }   
       
    public TripleDES(String mode) throws Exception {   
        if ("ECB".equals(mode)) {   
//          cipher = Cipher.getInstance(KEY_ALGORITHM);   
            cipher = Cipher.getInstance(CIPHER_ALGORITHM_ECB);   
            keyGen = KeyGenerator.getInstance(KEY_ALGORITHM);   
            secretKey = keyGen.generateKey();   
        } else if("CBC".equals(mode)) {   
            cipher = Cipher.getInstance(CIPHER_ALGORITHM_CBC);   
            keyGen = KeyGenerator.getInstance(KEY_ALGORITHM);   
            DESedeKeySpec spec = new DESedeKeySpec(keyGen.generateKey().getEncoded());   
            secretKey2 = SecretKeyFactory.getInstance(KEY_ALGORITHM).generateSecret(spec);   
        }   
    }   
    /**  
     * 加密  
     * @param str  
     * @return  
     * @throws Exception  
     */   
    public byte[] encrypt(String str) throws Exception {   
        cipher.init(Cipher.ENCRYPT_MODE, secretKey);   
        return encryptData = cipher.doFinal(str.getBytes());   
    }   
    /**  
     * 解密  
     * @param encrypt  
     * @return  
     * @throws Exception  
     */   
    public byte[] decrypt(byte[] encrypt) throws Exception {   
        cipher.init(Cipher.DECRYPT_MODE, secretKey);   
        return encryptData = cipher.doFinal(encrypt);   
    }   
    byte[] getIV() {   
        return "administ".getBytes();   
    }   
    /**  
     * 加密  
     * @param str  
     * @return  
     * @throws Exception  
     */   
    public byte[] encrypt2(String str) throws Exception {   
        cipher.init(Cipher.ENCRYPT_MODE, secretKey2, new IvParameterSpec(getIV()));   
        return encryptData = cipher.doFinal(str.getBytes());   
    }   
    /**  
     * 解密  
     * @param encrypt  
     * @return  
     * @throws Exception  
     */   
    public byte[] decrypt2(byte[] encrypt) throws Exception {   
        cipher.init(Cipher.DECRYPT_MODE, secretKey2, new IvParameterSpec(getIV()));   
        return encryptData = cipher.doFinal(encrypt);   
    }   
}