将ip转为整数以及整数转为ip的java实现

一个ip地址用字符串保存,长度为(7-15)也就是(14-30bytes),而用int保存只需要4bytes,所以下面的代码:

/** * ip字符串转整数 * ip是.分割的整数字符串,按照r进制转十进制的规律,按权相加求和,这里的权是256. * @param ip * @return */public int ip2Int(String ip){if(null == ip || "".equals(ip.trim()) || !checkIP(ip)) return 0;String[] ipStrs = ip.split("\\.");//分割ipint result = 0;for(int i = 0;i < 4;i ++){Integer ipSubInteger = Integer.parseInt(ipStrs[i]);if(ipSubInteger > 255) {//正则验证不能为负数result = 0;break;}result += (ipSubInteger << (24 - i * 8));}return result;}/*正则验证ip*/private boolean checkIP(String ip){return ip.matches("\\d{1,3}(\\.\\d{1,3}){3}");}/** * 整数转ip * @param ip * @return */public String int2Ip(int ip){StringBuilder builder = new StringBuilder(String.valueOf(ip >>> 24));builder.append(".");builder.append(String.valueOf((ip & 0X00FFFFFF) >>> 16));builder.append(".");builder.append(String.valueOf((ip & 0X0000FFFF) >>> 8));builder.append(".");builder.append(String.valueOf(ip & 0X000000FF));return builder.toString();}