去除字符串中的控制字符

/**
     * 去除控制字符,保证数据正确
     * */
    private String changeCtlChar(String vehicleNo){
        String value = "";
        if(vehicleNo == null){
            return value;
        }
         String[] chars = stringToAscii(vehicleNo).split(",");
         StringBuffer sbu = new StringBuffer(); 
         for (int i = 0; i < chars.length; i++) {  
             if(Integer.parseInt(chars[i]) > 31 && Integer.parseInt(chars[i]) != 127){                 
                 if(i != chars.length - 1)  
                 {  
                     sbu.append(Integer.parseInt(chars[i])).append(",");  
                 }  
                 else {  
                     sbu.append(Integer.parseInt(chars[i]));  
                 }  
             }
            } 
         value = asciiToString(sbu.toString());
         return value;
    }

    /**
     * String转ASCII
     * */
    private  String stringToAscii(String value)  
    {  
        StringBuffer sbu = new StringBuffer();  
        char[] chars = value.toCharArray();   
        for (int i = 0; i < chars.length; i++) {  
            if(i != chars.length - 1)  
            {  
                sbu.append((int)chars[i]).append(",");  
            }  
            else {  
                sbu.append((int)chars[i]);  
            }  
        }  
        return sbu.toString();  
    }  
    /**
     * ASCII转String
     * */
    private String asciiToString(String value)  
    {  
        StringBuffer sbu = new StringBuffer();  
        String[] chars = value.split(",");  
        for (int i = 0; i < chars.length; i++) {  
            sbu.append((char) Integer.parseInt(chars[i]));  
        }  
        return sbu.toString();  
    }