Java的Ip操作工具类

Java的Ip操作工具类教程

在 web 项目中，有的时候，我们需要获取相应的 ip 地址，然后对该 ip 地址做一些控制，比如 白名单啊，黑名单啊啥的，限制一部分 ip 做一些事情等等。前提是我们的项目是 web 项目。

IpUtil

package net.haicoder;
import java.util.regex.Pattern;
import javax.servlet.http.HttpServletRequest;
/**
 * @author 嗨客网
 * @description
 */
public class IpUtil {
    /**
     * 逗号,分隔
     */
    static final Pattern COMMA_PATTERN = Pattern.compile(",");
    private IpUtil() {
    }
    public static String getRemoteIp(HttpServletRequest request) {
        String ip = request.getHeader("x-forwarded-for");
        if (isNotIp(ip)) {
            ip = request.getHeader("Proxy-Client-IP");
        }
        if (isNotIp(ip)) {
            ip = request.getHeader("WL-Proxy-Client-IP");
        }
        if (isNotIp(ip)) {
            ip = request.getRemoteAddr();
        }
        if (isIp(ip)) {
            ip = COMMA_PATTERN.split(ip)[0];
        }
        return ip;
    }
    /**
     * 判断ip地址是正确的
     * @param ip ip地址
     * @return true-是，false-否
     */
    private static boolean isIp(String ip) {
        return !isNotIp(ip);
    }
    /**
     * 判断ip地址是不正确的
     * @param ip ip地址
     * @return true-是，false-否
     */
    private static boolean isNotIp(String ip) {
        return ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip);
    }
    public static long ipToLong(String ip) {
        int firstDot = ip.indexOf('.');
        int secDot = ip.indexOf('.', firstDot + 1);
        int thirdDot = ip.indexOf('.', secDot + 1);
        if (-1 == firstDot || -1 == secDot || -1 == thirdDot) {
            throw new IllegalArgumentException("illegal argument");
        }
        String firstStr = ip.substring(0, firstDot);
        String secStr = ip.substring(firstDot + 1, secDot);
        String thirdStr = ip.substring(secDot + 1, thirdDot);
        String fourthStr = ip.substring(thirdDot + 1, ip.length());
        long firstLong = Long.parseLong(firstStr);
        firstLong = firstLong << 24;
        long secLong = Long.parseLong(secStr);
        secLong = secLong << 16;
        long thirdLong = Long.parseLong(thirdStr);
        thirdLong = thirdLong << 8;
        long fourthLong = Long.parseLong(fourthStr);
        return firstLong + secLong + thirdLong + fourthLong;
    }
    public static String longToIp(long ipLong) {
        long temp = 0;
        long first = ipLong / (1 << 24);
        temp = ipLong % (1 << 24);
        long sec = temp / (1 << 16);
        temp = temp % (1 << 16);
        long third = temp / (1 << 8);
        temp = temp % (1 << 8);
        long fourth = temp;
        StringBuilder sb = new StringBuilder();
        sb.append(first).append(".").append(sec).append(".").append(third).append(".").append(fourth);
        return sb.toString();
    }
}