记录一个获取ip地址的工具类

package com.hf.hantopy.utils;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.http.HttpServletRequest;
import java.io.IOException;

/**
 * 常用获取客户端信息的工具
 *
 */
public final class NetworkUtil {
    /**
     * Logger for this class
     */
    private static Logger logger = LoggerFactory.getLogger(NetworkUtil.class);

    /**
     * 获取请求主机IP地址,如果通过代理进来，则透过防火墙获取真实IP地址;
     *
     * @param request
     * @return
     * @throws IOException
     */
    public final static String getIpAddress(HttpServletRequest request) {
        // 获取请求主机IP地址,如果通过代理进来，则透过防火墙获取真实IP地址
        try {
            String ip = request.getHeader("X-Forwarded-For");
            if (logger.isInfoEnabled()) {
                logger.info("getIpAddress(HttpServletRequest) - X-Forwarded-For - String ip=" + ip);
            }

            if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getHeader("Proxy-Client-IP");
                    if (logger.isInfoEnabled()) {
                        logger.info("getIpAddress(HttpServletRequest) - Proxy-Client-IP - String ip=" + ip);
                    }
                }
                if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getHeader("WL-Proxy-Client-IP");
                    if (logger.isInfoEnabled()) {
                        logger.info("getIpAddress(HttpServletRequest) - WL-Proxy-Client-IP - String ip=" + ip);
                    }
                }
                if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getHeader("HTTP_CLIENT_IP");
                    if (logger.isInfoEnabled()) {
                        logger.info("getIpAddress(HttpServletRequest) - HTTP_CLIENT_IP - String ip=" + ip);
                    }
                }
                if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getHeader("HTTP_X_FORWARDED_FOR");
                    if (logger.isInfoEnabled()) {
                        logger.info("getIpAddress(HttpServletRequest) - HTTP_X_FORWARDED_FOR - String ip=" + ip);
                    }
                }
                if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
                    ip = request.getRemoteAddr();
                    if (logger.isInfoEnabled()) {
                        logger.info("getIpAddress(HttpServletRequest) - getRemoteAddr - String ip=" + ip);
                    }
                }
            } else if (ip.length() > 15) {
                String[] ips = ip.split(",");
                for (int index = 0; index < ips.length; index++) {
                    String strIp = (String) ips[index];
                    if (!("unknown".equalsIgnoreCase(strIp))) {
                        ip = strIp;
                        break;
                    }
                }
            }
            return ip;
        } catch (Exception e) {
            logger.error("obtain ip address fail.....",e.getMessage(),e);
        }
        return null;
    }
}