java程序一直需要獲取物理機的ip，寫了一個ip的工具類，感覺日常所需夠了

import javax.servlet.http.HttpServletRequest;
import java.net.InetAddress;
import java.net.UnknownHostException;/*** IP 工具類*/
public class IpUtil {public static String getIpAddr(HttpServletRequest request) {if (request == null) {return "unknown";}String ip = request.getHeader("x-forwarded-for");if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {ip = request.getHeader("Proxy-Client-IP");}if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {ip = request.getHeader("X-Forwarded-For");}if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {ip = request.getHeader("WL-Proxy-Client-IP");}if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {ip = request.getHeader("X-Real-IP");}if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {ip = request.getRemoteAddr();}return "0:0:0:0:0:0:0:1".equals(ip) ? "127.0.0.1" : ip;}public static boolean internalIp(String ip) {byte[] addr = textToNumericFormatV4(ip);return internalIp(addr) || "127.0.0.1".equals(ip);}private static boolean internalIp(byte[] addr) {final byte b0 = addr[0];final byte b1 = addr[1];// 10.x.x.x/8final byte SECTION_1 = 0x0A;// 172.16.x.x/12final byte SECTION_2 = (byte) 0xAC;final byte SECTION_3 = (byte) 0x10;final byte SECTION_4 = (byte) 0x1F;// 192.168.x.x/16final byte SECTION_5 = (byte) 0xC0;final byte SECTION_6 = (byte) 0xA8;switch (b0) {case SECTION_1:return true;case SECTION_2:if (b1 >= SECTION_3 && b1 <= SECTION_4) {return true;}case SECTION_5:switch (b1) {case SECTION_6:return true;}default:return false;}}/*** 將IPv4地址轉換成字節** @param text IPv4地址* @return byte 字節*/public static byte[] textToNumericFormatV4(String text) {if (text.length() == 0) {return null;}byte[] bytes = new byte[4];String[] elements = text.split("\\.", -1);try {long l;int i;switch (elements.length) {case 1:l = Long.parseLong(elements[0]);if ((l < 0L) || (l > 4294967295L)) {return null;}bytes[0] = (byte) (int) (l >> 24 & 0xFF);bytes[1] = (byte) (int) ((l & 0xFFFFFF) >> 16 & 0xFF);bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);bytes[3] = (byte) (int) (l & 0xFF);break;case 2:l = Integer.parseInt(elements[0]);if ((l < 0L) || (l > 255L)) {return null;}bytes[0] = (byte) (int) (l & 0xFF);l = Integer.parseInt(elements[1]);if ((l < 0L) || (l > 16777215L)) {return null;}bytes[1] = (byte) (int) (l >> 16 & 0xFF);bytes[2] = (byte) (int) ((l & 0xFFFF) >> 8 & 0xFF);bytes[3] = (byte) (int) (l & 0xFF);break;case 3:for (i = 0; i < 2; ++i) {l = Integer.parseInt(elements[i]);if ((l < 0L) || (l > 255L)) {return null;}bytes[i] = (byte) (int) (l & 0xFF);}l = Integer.parseInt(elements[2]);if ((l < 0L) || (l > 65535L)) {return null;}bytes[2] = (byte) (int) (l >> 8 & 0xFF);bytes[3] = (byte) (int) (l & 0xFF);break;case 4:for (i = 0; i < 4; ++i) {l = Integer.parseInt(elements[i]);if ((l < 0L) || (l > 255L)) {return null;}bytes[i] = (byte) (int) (l & 0xFF);}break;default:return null;}} catch (NumberFormatException e) {return null;}return bytes;}public static String getHostIp() {try {return InetAddress.getLocalHost().getHostAddress();} catch (UnknownHostException e) {}return "127.0.0.1";}public static String getHostName() {try {return InetAddress.getLocalHost().getHostName();} catch (UnknownHostException e) {}return "未知";}
}