信息计算2019级2班5号张欢

张欢

线上提交3.11-3.14

张欢

1. import javax.crypto.BadPaddingException;
   
2. import javax.crypto.Cipher;
   
3. import javax.crypto.IllegalBlockSizeException;
   
4. import javax.crypto.KeyGenerator;
   
5. import javax.crypto.NoSuchPaddingException;
   
6. import java.io.UnsupportedEncodingException;
   
7. import java.nio.charset.Charset;
   
8. import java.security.InvalidKeyException;
   
9. import java.security.NoSuchAlgorithmException;
   
10. import java.security.SecureRandom;
    
11. import java.util.Base64;
    
12. import java.util.Base64.Encoder;
    
13. import javax.crypto.SecretKey;
    
14. 
    
15. public class AESTest {
    
16.         static final String ALGORITHM="AES";
    
17.         public static SecretKey generatekey() throws NoSuchAlgorithmException {
    
18.                 KeyGenerator secretGenerator=KeyGenerator.getInstance(ALGORITHM);
    
19.                 SecureRandom secureRandom=new SecureRandom();
    
20.                 secretGenerator.init(secureRandom);
    
21.                 SecretKey secretKey=secretGenerator.generateKey();
    
22.                 return secretKey;
    
23.         }
    
24.         final static String charsetName="UTF-8";
    
25.         static Charset charset=Charset.forName("UTF-8");
    
26.         //编码
    
27.         public static byte[] encrypt(String content,SecretKey secretKey) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException {
    
28.                 byte[] encryptResult = aes(content.getBytes(charset),Cipher.ENCRYPT_MODE,secretKey);
    
29.                 Encoder enc = Base64.getEncoder();
    
30.             String encStr = enc.encodeToString(encryptResult);
    
31.             System.out.println("加密后base64编码的密文 ： " + encStr);  
    
32.             return encryptResult;
    
33.         }
    
34.         //解码
    
35.         public static String decrypt(byte[] contentArray,SecretKey secretKey) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {
    
36.                 byte[] result=aes(contentArray,Cipher.DECRYPT_MODE,secretKey);
    
37.                 return new String(result,charsetName);
    
38.         }
    
39.         private static byte[] aes(byte[] contentArray,int mode,SecretKey secretKey) throws NoSuchAlgorithmException, NoSuchPaddingException, InvalidKeyException, IllegalBlockSizeException, BadPaddingException {
    
40.                 Cipher cipher=Cipher.getInstance(ALGORITHM);
    
41.                 cipher.init(mode, secretKey);
    
42.                 byte[] result=cipher.doFinal(contentArray);
    
43.                 return result;
    
44.         }
    
45.         public static void main(String[] args) throws InvalidKeyException, NoSuchAlgorithmException, NoSuchPaddingException, IllegalBlockSizeException, BadPaddingException, UnsupportedEncodingException {
    
46.                 String content="不想写代码了";
    
47.                 SecretKey secretKey=generatekey();
    
48.                 byte[] encryptResult=encrypt(content,secretKey);
    
49.                 String decryptResult=decrypt(encryptResult,secretKey);
    
50.                 System.out.println("解密后的结果为："+decryptResult);
    
51.         }
    
52. }
    

复制代码