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package com.jiax3.common.util; import java.net.Inet4Address; import java.net.InetAddress; import java.net.NetworkInterface; import java.net.SocketException; import java.util.Enumeration; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /* This utility provides methods to either convert an IPv4 address to its long format or a 32bit dotted format. * * @author Michael * Created on 2013.09.29 */ public class IPv4 { private static Logger logger = LoggerFactory.getLogger(IPv4.class); private static String hostAddress; static { hostAddress = getHostAddress(); } /** * Returns the long format of the provided IP address. * * @param ipAddress * the IP address * @return the long format of <code>ipAddress</code> * @throws IllegalArgumentException * if <code>ipAddress</code> is invalid */ public static long toLong(String ipAddress) { if (ipAddress == null || ipAddress.isEmpty()) { throw new IllegalArgumentException( “ip address cannot be null or empty”); } String[] octets = ipAddress.split(java.util.regex.Pattern.quote(“.”)); if (octets.length != 4) { throw new IllegalArgumentException(“invalid ip address”); } long ip = 0; for (int i = 3; i >= 0; i–) { long octet = Long.parseLong(octets[3 – i]); if (octet > 255 || octet < 0) { throw new IllegalArgumentException(“invalid ip address”); } ip |= octet << (i * 8); } return ip; } /** * Returns the 32bit dotted format of the provided long ip. * * @param ip * the long ip * @return the 32bit dotted format of <code>ip</code> * @throws IllegalArgumentException * if <code>ip</code> is invalid */ public static String toString(long ip) { // if ip is bigger than 255.255.255.255 or smaller than 0.0.0.0 if (ip > 4294967295l || ip < 0) { throw new IllegalArgumentException(“invalid ip”); } StringBuilder ipAddress = new StringBuilder(); for (int i = 3; i >= 0; i–) { int shift = i * 8; ipAddress.append((ip & (0xff << shift)) >> shift); if (i > 0) { ipAddress.append(“.”); } } return ipAddress.toString(); } /** * 获取主机ip * @return * @throws SocketException */ public static String getHostAddress() { try { Enumeration<NetworkInterface> netInterfaces = NetworkInterface.getNetworkInterfaces(); while (netInterfaces.hasMoreElements()) { NetworkInterface nif = netInterfaces.nextElement(); Enumeration<InetAddress> iparray = nif.getInetAddresses(); while (iparray.hasMoreElements()) { InetAddress ip = (InetAddress) iparray.nextElement(); if (ip != null && ip instanceof Inet4Address && !ip.getHostAddress().equals(“127.0.0.1”)){ return ip.getHostAddress(); } } } } catch (Exception e) { logger.error(“IPv4 static method getHostAddress error: {}”, e); } return null; } /** * 获取缓存静态主机ip * @return */ public static String getCacheHostAddress() { return hostAddress; } }