1 //======================================================================== 2 //$Id: RegexRule.java 966 2008-04-17 13:53:44Z gregw $ 3 //Copyright 2004-2005 Mort Bay Consulting Pty. Ltd. 4 //------------------------------------------------------------------------ 5 //Licensed under the Apache License, Version 2.0 (the "License"); 6 //you may not use this file except in compliance with the License. 7 //You may obtain a copy of the License at 8 //http://www.apache.org/licenses/LICENSE-2.0 9 //Unless required by applicable law or agreed to in writing, software 10 //distributed under the License is distributed on an "AS IS" BASIS, 11 //WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 //See the License for the specific language governing permissions and 13 //limitations under the License. 14 //======================================================================== 15 package org.mortbay.jetty.handler.rewrite; 16 17 import java.io.IOException; 18 import java.util.regex.Matcher; 19 import java.util.regex.Pattern; 20 21 import javax.servlet.http.HttpServletRequest; 22 import javax.servlet.http.HttpServletResponse; 23 24 25 /** 26 * Abstract rule to use as a base class for rules that match with a regular expression. 27 */ 28 public abstract class RegexRule extends Rule 29 { 30 protected Pattern _regex; 31 32 /* ------------------------------------------------------------ */ 33 /** 34 * Sets the regular expression string used to match with string URI. 35 * 36 * @param regex the regular expression. 37 */ 38 public void setRegex(String regex) 39 { 40 _regex=Pattern.compile(regex); 41 } 42 43 /* ------------------------------------------------------------ */ 44 /** 45 * @return get the regular expression 46 */ 47 public String getRegex() 48 { 49 return _regex==null?null:_regex.pattern(); 50 } 51 52 53 /* ------------------------------------------------------------ */ 54 public String matchAndApply(String target, HttpServletRequest request, HttpServletResponse response) throws IOException 55 { 56 Matcher matcher=_regex.matcher(target); 57 boolean matches = matcher.matches(); 58 if (matches) 59 return apply(target,request,response, matcher); 60 return null; 61 } 62 63 /* ------------------------------------------------------------ */ 64 /** 65 * Apply this rule to the request/response pair. 66 * Called by {@link #matchAndApply(String, HttpServletRequest, HttpServletResponse)} if the regex matches. 67 * @param target field to attempt match 68 * @param request request object 69 * @param response response object 70 * @param matcher The Regex matcher that matched the request (with capture groups available for replacement). 71 * @return The target (possible updated). 72 * @throws IOException exceptions dealing with operating on request or response objects 73 */ 74 protected abstract String apply(String target, HttpServletRequest request, HttpServletResponse response, Matcher matcher) throws IOException; 75 76 77 /* ------------------------------------------------------------ */ 78 /** 79 * Returns the regular expression string. 80 */ 81 public String toString() 82 { 83 return super.toString()+"["+_regex+"]"; 84 } 85 }