* @return 
      */  
    public String decryptStr(String strMi) {  
       BASE64Decoder base64De = new BASE64Decoder();  
       byte [] byteMing = null ;  
       byte [] byteMi = null ;  
       String strMing = "" ;  
       try {  
           byteMi = base64De.decodeBuffer(strMi);  
           byteMing = this .decryptByte(byteMi);  
           strMing = new String(byteMing, "UTF8" );  
       } catch (Exception e) {  
           throw new RuntimeException(  
                  "Error initializing SqlMap class. Cause: " + e);  
       } finally {  
           base64De = null ;  
           byteMing = null ;  
           byteMi = null ;  
       }  
       return strMing;  
    }