字符串類型ip與數值型ip地址相互轉換

    /**
     * 返回Integer類型的ip地址
     * @return 
     */
    private static Integer ipToInt(){
        String ip="192.168.1.201";
        StringTokenizer token=new StringTokenizer(ip, ".");
        Integer result=0;
        result +=Integer.parseInt(token.nextToken())<<24;
        result +=Integer.parseInt(token.nextToken())<<16;
        result += Integer.parseInt(token.nextToken())<<8;
        result +=Integer.parseInt(token.nextToken());
        return result;
    }
    
    /**
     * 將數值型的ip地址轉換爲字符串類型
     * @param ip 數值型的ip地址
     * @return
     */
    private static String intToIp(Integer ip){
        StringBuilder sb=new StringBuilder();
        sb.append(ip>>>24);
        sb.append(".");
        sb.append(String.valueOf((ip&0x00FFFFFF)>>>16));
        sb.append(".");
        sb.append(String.valueOf((ip&0x0000FFFF)>>>8));
        sb.append(".");
        sb.append(String.valueOf(ip&0x000000FF));
        return sb.toString();
    }