從request請求頭獲得請求用戶的IP與IP驗證

	 /** 
	   * 獲取用戶真實IP地址，如果通過了多級反向代理的話，X-Forwarded-For的值並不止一個，而是一串IP值，
	   * 取X-Forwarded-For中第一個非unknown的有效IP字符串。 
	   * 如：X-Forwarded-For：192.168.1.110, 192.168.1.120, 192.168.1.130, 
	   * 192.168.1.100 
	   * 
	   * 用戶真實IP爲： 192.168.1.110 
	   * 
	   * @param request 
	   * @return 
	   */
	  public static String getIpAddress(HttpServletRequest request) { 
		  String ip = request.getHeader("X-Forwarded-For");  
	        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 (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("HTTP_CLIENT_IP");  
	            }  
	            if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {  
	                ip = request.getHeader("HTTP_X_FORWARDED_FOR");  
	            }  
	            if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ip)) {  
	                ip = request.getRemoteAddr();  
	            }  
	        } 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; 
	  }

驗證IP格式

/**通過originalIP 校驗ip是否有效	<br>
	 * 正確originalIP 可能的格式，如：<br>
	 * 10.2.0.1  <br>
	 * 10.2.0.* <br>
	 * 10.2.*.*<br>
	 * 10.*.*.*<br>
	 * *.*.*.*<br>
	 * ip 的格式一定爲10.2.0.2
	 *  */
	public static Boolean validIp(String originalIP,String ip){
		if (!StringUtils.hasText(originalIP)) {
			return true;
		}
		originalIP = originalIP.trim();
		if (!StringUtils.hasText(ip)) {
			return false;
		}
		ip = ip.trim();
		
		String ipReg = "^((1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|[1-9])|\\*)\\."
				  + "((1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)|\\*)\\."
			      + "((1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)|\\*)\\."
			      + "((1\\d{2}|2[0-4]\\d|25[0-5]|[1-9]\\d|\\d)|\\*)$";
		/**校驗ip的格式*/
		Pattern pattern = Pattern.compile(ipReg);
		Matcher ipMatcher = pattern.matcher(ip);
		if (!ipMatcher.matches()) {
			return false;
		}
		/**校驗originalIP 的格式*/
		Pattern oriPattern = Pattern.compile(ipReg);
		Matcher oriMatcher = oriPattern.matcher(originalIP);
		if (!oriMatcher.matches()) {
			return false;
		}

		/**originalIP與ip 相同*/
		if(originalIP.equals(ip)){
			return true;
		}
		
		/**校驗ip是否處在originalIP段內*/
		
		String[] oriIpArr = originalIP.split("\\.");
		String[] ipArr = ip.split("\\.");
		Boolean hasStar=false;
		String star="*";
		for(int i=0;i<oriIpArr.length;i++){
			String oriIp = oriIpArr[i];
			boolean flag = oriIp.equals(star) ;
			if(flag){
				hasStar=flag;
			}
			if(hasStar && !flag){
				return false;
			}
			if(!ipArr[i].equals(oriIp) && !oriIp.equals(star)){
				return false;
			}
		}
		return true;
	}