java 字符串 asc 加密解密

    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;  
            }  
          }  
    }