1 package com.tem1.util;
2
3 import java.security.InvalidKeyException;
4 import java.security.NoSuchAlgorithmException;
5 import java.security.Security;
6
7
8 import javax.crypto.BadPaddingException;
9 import javax.crypto.Cipher;
10 import javax.crypto.IllegalBlockSizeException;
11 import javax.crypto.KeyGenerator;
12 import javax.crypto.NoSuchPaddingException;
13 import javax.crypto.SecretKey;
14
15 import com.sun.crypto.provider.SunJCE;
16
17 public class EncrypDES {
18
19 //KeyGenerator 提供对称密钥生成器的功能，支持各种算法 如：DES DESede(3DES) AES
20 private KeyGenerator keygen;
21 //SecretKey 负责保存对称密钥
22 private SecretKey deskey;
23 //Cipher负责完成加密或解密工作
24 private Cipher c;
25 //该字节数组负责保存加密的结果
26 private byte[] cipherByte;
27
28 public EncrypDES() throws NoSuchAlgorithmException, NoSuchPaddingException{
29 Security.addProvider(new SunJCE());
30 //实例化支持DES算法的密钥生成器(算法名称命名需按规定，否则抛出异常)
31 // keygen = KeyGenerator.getInstance("DESede");
32 keygen = KeyGenerator.getInstance("DES");
33 //生成密钥
34 deskey = keygen.generateKey();
35 System.out.println("Key :"+deskey);
36 //生成Cipher对象,指定其支持的DES算法
37 c = Cipher.getInstance("DES");
38 }
39
40 /**
41 * 对字符串加密
42 *
43 * @param str
44 * @return
45 * @throws InvalidKeyException
46 * @throws IllegalBlockSizeException
47 * @throws BadPaddingException
48 */
49 public byte[] Encrytor(String str) throws InvalidKeyException,
50 IllegalBlockSizeException, BadPaddingException {
51 // 根据密钥，对Cipher对象进行初始化，ENCRYPT_MODE表示加密模式
52 c.init(Cipher.ENCRYPT_MODE, deskey);
53
54 byte[] src = str.getBytes();
55 // 加密，结果保存进cipherByte
56 cipherByte = c.doFinal(src);
57 return cipherByte;
58 }
59
60 /**
61 * 对字符串解密
62 *
63 * @param buff
64 * @return
65 * @throws InvalidKeyException
66 * @throws IllegalBlockSizeException
67 * @throws BadPaddingException
68 */
69 public byte[] Decryptor(byte[] buff) throws InvalidKeyException,
70 IllegalBlockSizeException, BadPaddingException {
71 // 根据密钥，对Cipher对象进行初始化，DECRYPT_MODE表示加密模式
72 c.init(Cipher.DECRYPT_MODE, deskey);
73 cipherByte = c.doFinal(buff);
74 return cipherByte;
75 }
76
77 /**
78 * @param args
79 * @throws NoSuchPaddingException
80 * @throws NoSuchAlgorithmException
81 * @throws BadPaddingException
82 * @throws IllegalBlockSizeException
83 * @throws InvalidKeyException
84 */
85 public static void main(String[] args) throws Exception {
86 EncrypDES de1 = new EncrypDES();
87 String msg ="明天七点出发";
88 byte[] encontent = de1.Encrytor(msg);
89 byte[] decontent = de1.Decryptor(encontent);
90 System.out.println("明文是:" + msg);
91 System.out.println("加密后:" + new String(encontent));
92 System.out.println("解密后:" + new String(decontent));
93 }
94
95 }
