java 字符串 asc 加密解密详解编程语言

    package com;   
       
    public class MD5Test {   
       
        /**  
         * @param args  
         */   
        public static void main(String[] args) {   
            System.out.println(decrypt("137%128%143%145%124%144%135%143%76%"));   
               
            System.out.println(encrypt("frontdev"));   
        }   
           
        /**  
           *用户名解密  
           *@param ssoToken 字符串  
           *@return String 返回加密字符串  
          */   
          public static String decrypt(String ssoToken)   
          {   
            try   
            {   
              String name = new String();   
              java.util.StringTokenizer st=new java.util.StringTokenizer(ssoToken,"%");   
              while (st.hasMoreElements()) {   
                int asc =  Integer.parseInt((String)st.nextElement()) - 27;   
                name = name + (char)asc;   
              }   
       
              return name;   
            }catch(Exception e)   
            {   
              e.printStackTrace() ;   
              return null;   
            }   
          }   
       
          /**  
           *用户名加密  
           *@param ssoToken 字符串  
           *@return String 返回加密字符串  
          */   
          public static String encrypt(String ssoToken)   
          {   
            try   
            {   
              byte[] _ssoToken = ssoToken.getBytes("ISO-8859-1");   
              String name = new String();   
             // char[] _ssoToken = ssoToken.toCharArray();   
              for (int i = 0; i < _ssoToken.length; i++) {   
                  int asc = _ssoToken[i];   
                  _ssoToken[i] = (byte) (asc + 27);   
                  name = name + (asc + 27) + "%";   
              }   
              return name;   
            }catch(Exception e)   
            {   
              e.printStackTrace() ;   
              return null;   
            }   
          }   
    }