DES加密解密实现

 1 package com.liuhq.o2o.utils;
 2 
 3 import java.security.Key;
 4 import java.security.SecureRandom;
 5 
 6 import javax.crypto.Cipher;
 7 import javax.crypto.KeyGenerator;
 8 
 9 import sun.misc.BASE64Decoder;
10 import sun.misc.BASE64Encoder;
11 
12 @SuppressWarnings("restriction")
13 public class DESUtil {
14 
15     private static Key key;
16     private static String KEY_STR = "myKey";
17     private static String CHARSETNAME = "UTF-8";
18     private static String ALGORITHM = "DES";
19 
20     static {
21         try {
22             // 生成DES算法对象
23             KeyGenerator generator = KeyGenerator.getInstance(ALGORITHM);
24             // 运行SHA1安全策略
25             SecureRandom secureRandom = SecureRandom.getInstance("SHA1PRNG");
26             //设置上秘钥种子
27             secureRandom.setSeed(KEY_STR.getBytes());
28             //初始化基于SHA1的算法对象
29             generator.init(secureRandom);
30             // 生成秘钥对象
31             key = generator.generateKey();
32             generator = null;
33         } catch (Exception e) {
34             throw new RuntimeException(e);
35         }
36     }
37     
38     /**
39      * 加密
40      * @param str
41      * @return
42      */
43     public static String getEncryptString(String str) {
44         // 基于BADE64编码  接受byte[]并转化为String
45         BASE64Encoder base64encoder = new BASE64Encoder();
46         try {
47             // 按UTF8编码
48             byte[] bytes = str.getBytes(CHARSETNAME);
49             // 获取加密对象
50             Cipher cipher = Cipher.getInstance(ALGORITHM);
51             // 初始化密码信息
52             cipher.init(Cipher.ENCRYPT_MODE, key);
53             // 加密
54             byte[] doFinal = cipher.doFinal(bytes);
55             // byte[] to encode好的string返回
56             return base64encoder.encode(doFinal);
57         } catch (Exception e) {
58             // TODO: handle exception
59             throw new RuntimeException(e);
60         }
61     }
62 
63     /**
64      * 解密
65      * @param str
66      * @return
67      */
68     public static String getDecryptString(String str) {
69         // 基于BADE64编码  接受byte[]并转化为String
70         
71         BASE64Decoder base64decoder = new BASE64Decoder();
72         try {
73             //将字符串decode成byte[]
74             byte[] bytes = base64decoder.decodeBuffer(str);
75             // 获取加密对象
76             Cipher cipher = Cipher.getInstance(ALGORITHM);
77             // 初始化密码信息
78             cipher.init(Cipher.DECRYPT_MODE, key);
79             //解密
80             byte[] doFinal = cipher.doFinal(bytes);
81             //返回解密之后的信息
82             return new String(doFinal, CHARSETNAME);
83         } catch (Exception e) {
84             // TODO: handle exception
85             throw new RuntimeException(e);
86         }
87     }
88     
89     public static void main(String[] args) {
90         System.out.println(getEncryptString("root"));
91         System.out.println(getEncryptString("123456"));
92        
93       
94     }
95 
96 }