package com.dy.encryption.symmetric;import sun.misc.BASE64Decoder;import sun.misc.BASE64Encoder;import javax.crypto.Cipher;import javax.crypto.SecretKey;import javax.crypto.SecretKeyFactory;import javax.crypto.spec.PBEKeySpec;import javax.crypto.spec.PBEParameterSpec;import java.security.Key;import java.util.Random;/** * PBE——Password-based encryption（基于密码加密）。 (想了解更多的加密，解密算法和数字签名实现，请游览本人博客) * 其特点在于口令由用户自己掌管，不借助任何物理媒体；采用随机数（这里我们叫做盐）杂凑多重加密等方法保证数据的安全性。 * 是一种简便的加密方式。 */public class PBEdemo {    /**     * 支持以下任意一种算法     * 
     * 
     * PBEWithMD5AndDES     * PBEWithMD5AndTripleDES     * PBEWithSHA1AndDESede     * PBEWithSHA1AndRC2_40     * 
     */    public static final String ALGORITHM = "PBEWITHMD5andDES";    /**     * 盐初始化     *     * @return     * @throws Exception     */    public static byte[] initSalt() throws Exception {        byte[] salt = new byte[8];        Random random = new Random();        random.nextBytes(salt);        return salt;    }    /**     * 转换密钥
     *     * @param password     * @return     * @throws Exception     */    private static Key toKey(String password) throws Exception {        PBEKeySpec keySpec = new PBEKeySpec(password.toCharArray());        SecretKeyFactory keyFactory = SecretKeyFactory.getInstance(ALGORITHM);        SecretKey secretKey = keyFactory.generateSecret(keySpec);        return secretKey;    }    /**     * 加密     *     * @param data     数据     * @param password 密码     * @param salt     盐     * @return     * @throws Exception     */    public static String encrypt(String data, String password, byte[] salt)            throws Exception {        Key key = toKey(password);        PBEParameterSpec paramSpec = new PBEParameterSpec(salt, 100);        Cipher cipher = Cipher.getInstance(ALGORITHM);        cipher.init(Cipher.ENCRYPT_MODE, key, paramSpec);        return new BASE64Encoder().encode(cipher.doFinal(data.getBytes("UTF-8")));    }    /**     * 解密     *     * @param data     数据     * @param password 密码     * @param salt     盐     * @return     * @throws Exception     */    public static String decrypt(String data, String password, byte[] salt)            throws Exception {        Key key = toKey(password);        PBEParameterSpec paramSpec = new PBEParameterSpec(salt, 100);        Cipher cipher = Cipher.getInstance(ALGORITHM);        cipher.init(Cipher.DECRYPT_MODE, key, paramSpec);        return new String(cipher.doFinal(new BASE64Decoder().decodeBuffer(data)));    }    public static void main(String[] args) {        try {            String input = "PBE";            String pwd = "dyyweb";            byte[] salt = PBEdemo.initSalt();            System.err.println("原文: " + input);            String encrypt_input = PBEdemo.encrypt(input, pwd, salt) ;            System.err.println("加密后: " + encrypt_input );            System.err.println("解密后: " + PBEdemo.decrypt(encrypt_input,pwd,salt));        } catch (Exception e) {            e.printStackTrace();        }    }}