Implement IP range filtering instances in java

The first reflection of OneCoder is to implement a filter, configure accessible IP rules, and match through regular expressions. You can access the system normally. If you do not use redirect, you can access the specified welcome page.

The entire code has no difficulty. The core is an IP rule validation function. Considering the simplicity of the configuration, that is, you are generally familiar with 192.168.1. * and 192.168.2.1-23. This configuration method supports full matching and range matching. OneCoder decides to use the sharding and resolution matching method. Rules are separated by semicolons. The code is implemented as follows:

The code is as follows:

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/*** IP rule regular expression processing tool class ** @ author OneCoder * @ date 1:23:09 on January 1, October 23, 2014 */public class IPRegexUtil { /** * Check whether the given IP address meets the specified rule   * * @ Author li_hongzhe @ nhn.com * @ Date 1:38:37, January 1, October 23, 2014 * @ Param ipStr * IP address to be verified * @ Param ipPattern * IP address matching rules. Supports * matching all and-matching ranges. Separate them with semicolons & lt; br & gt; * Example: 10.34.163. *; 10.34.162.1-128 * @ Return */ Public static boolean validateIP (String ipStr, String ipPattern ){ If (ipStr = null | ipPattern = null ){ Return false;       } String [] patternList = ipPattern. split (";"); For (String pattern: patternList ){ If (passValidate (ipStr, pattern )){ Return true;           }       } Return false;  } Private static boolean passValidate (String ipStr, String pattern ){ String [] ipStrArr = ipStr. split ("."); String [] patternArr = pattern. split ("."); If (ipStrArr. length! = 4 | patternArr. length! = 4 ){ Return false;       } Int end = ipStrArr. length; If (patternArr [3]. contains ("-")){ End = 3; String [] rangeArr = patternArr [3]. split ("-"); Int from = Integer. valueOf (rangeArr [0]). intValue (); Int to = Integer. valueOf (rangeArr [1]). intValue (); Int value = Integer. valueOf (ipStrArr [3]). intValue (); If (value & lt; from | value & gt; ){ Return false;           }       } For (int I = 0; I & lt; end; I ++ ){ If (patternArr [I]. equals ("*")){ Continue;           } If (! PatternArr [I]. equalsIgnoreCase (ipStrArr [I]) { Return false;           }       } Return true;  } }

The implementation filter is as follows:

The code is as follows:

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Import java. io. IOException; Import javax. servlet. filter; import javax. servlet. filterChain; import javax. servlet. filterConfig; import javax. servlet. servletException; import javax. servlet. servletRequest; import javax. servlet. servletResponse; import javax. servlet. http. httpServletRequest; import javax. servlet. http. httpServletResponse; /*** IP address filter. If the IP address is within the filter range, access is allowed. <Br> * if it is not within the specified range, the page is displayed. ** @ Author OneCoder * @ date October 24, 2014 9:54:33 */public class IPFilter implements Filter { Private String ipPattern; @ Override Public void destroy (){ // TODO Auto-generated method stub  } @ Override Public void doFilter (ServletRequest request, ServletResponse response, FilterChain filterChain) throws IOException, ServletException { String ip = request. getRemoteHost (); String reqUrl = (HttpServletRequest) request). getRequestURI (); If (reqUrl. contains ("forbidden ")){ FilterChain. doFilter (request, response ); Return;       } If (IPRegexUtil. validateIP (ip, ipPattern )){ FilterChain. doFilter (request, response ); } Else { (HttpServletResponse) response). sendRedirect ("/shurnim/forbidden ");       }  } @ Override Public void init (FilterConfig filterConfig) throws ServletException { This. ipPattern = filterConfig. getInitParameter ("ip-pattern ");  } Public String getIpPattern (){ Return ipPattern;  } Public void setIpPattern (String ipPattern ){ This. ipPattern = ipPattern;  } }

Web. the xml configuration is as follows: <pre class = "brush: xml"> <filter-name> IPFilter </filter-name> <filter-class> com. coderli. web. filter. ip. IPFilter </filter-class> <init-param> <param-name> ip-pattern </param-name> <param-value> 10.34.163.169; 10.34.163.1-254 </param-value> </init-param> </filter> <filter-mapping> <filter-name> IPFilter </filter-name> <url-pattern >/* </url-pattern> </filter-mapping> </pre>

The code does not seem to be well explained. At present, it seems that the requirements are met.