JavaアクセスIPの取得

JavaアクセスIPの取得
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import javax.servlet.http.HttpServletRequest;

/**
 *   IP
 */
public class IPUtil {
	/**
	 *        IP
	 * 
	 * @param request
	 *            HttpServletRequest     
	 * @return String
	 */
	public static String getIp(HttpServletRequest request) {
		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("WL-Proxy-Client-IP");
		}
		if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {
			ip = request.getRemoteAddr();
		}
		if (ip.indexOf(",") != -1) {
			String[] ips = ip.split(",");
			ip = ips[0].trim();
		}
		return ip;
	}
}