md5加密

import java.security.InvalidKeyException;   import java.security.NoSuchAlgorithmException;   import java.security.Security;     import javax.crypto.BadPaddingException;   import javax.crypto.Cipher;   import javax.crypto.IllegalBlockSizeException;   import javax.crypto.KeyGenerator;   import javax.crypto.NoSuchPaddingException;   import javax.crypto.SecretKey;import java.security.MessageDigest;   import java.security.NoSuchAlgorithmException;public class MD5 { public static String MD5(String inStr) {      MessageDigest md5 = null;      try {       md5 = MessageDigest.getInstance("MD5");      } catch (Exception e) {       System.out.println(e.toString());       e.printStackTrace();       return "";      }      char[] charArray = inStr.toCharArray();      byte[] byteArray = new byte[charArray.length];         for (int i = 0; i < charArray.length; i++)       byteArray[i] = (byte) charArray[i];         byte[] md5Bytes = md5.digest(byteArray);         StringBuffer hexValue = new StringBuffer();         for (int i = 0; i < md5Bytes.length; i++) {       int val = ((int) md5Bytes[i]) & 0xff;       if (val < 16)        hexValue.append("0");       hexValue.append(Integer.toHexString(val));      }         return hexValue.toString();     }        // 可逆的加密算法     public static String KL(String inStr) {      // String s = new String(inStr);      char[] a = inStr.toCharArray();      for (int i = 0; i < a.length; i++) {       a[i] = (char) (a[i] ^ 't');      }      String s = new String(a);      return s;     }        // 加密后解密     public static String JM(String inStr) {      char[] a = inStr.toCharArray();      for (int i = 0; i < a.length; i++) {       a[i] = (char) (a[i] ^ 't');      }      String k = new String(a);      return k;     }           // 测试主函数      public static void main(String args[]) {      String s = new String("20135102205118933MC84332&13111111111&票档次");      System.out.println("原始：" + s);      System.out.println("MD5后：" + MD5(s));      System.out.println("MD5后再加密：" + KL(MD5(s)));      System.out.println("解密为MD5后的：" + JM(KL(MD5(s))));   }    }