//========================================================================
//$Id: RegexRule.java 966 2008-04-17 13:53:44Z gregw $
//Copyright 2004-2005 Mort Bay Consulting Pty. Ltd.
//------------------------------------------------------------------------
//Licensed under the Apache License, Version 2.0 (the "License");
//you may not use this file except in compliance with the License.
//You may obtain a copy of the License at
//http://www.apache.org/licenses/LICENSE-2.0
//Unless required by applicable law or agreed to in writing, software
//distributed under the License is distributed on an "AS IS" BASIS,
//WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//See the License for the specific language governing permissions and
//limitations under the License.
//========================================================================
package org.mortbay.jetty.handler.rewrite;
import java.io.IOException;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
* Abstract rule to use as a base class for rules that match with a regular expression.
*/
public abstract class RegexRule extends Rule
{
protected Pattern _regex;
/* ------------------------------------------------------------ */
/**
* Sets the regular expression string used to match with string URI.
*
* @param regex the regular expression.
*/
public void setRegex(String regex)
{
_regex=Pattern.compile(regex);
}
/* ------------------------------------------------------------ */
/**
* @return get the regular expression
*/
public String getRegex()
{
return _regex==null?null:_regex.pattern();
}
/* ------------------------------------------------------------ */
public String matchAndApply(String target, HttpServletRequest request, HttpServletResponse response) throws IOException
{
Matcher matcher=_regex.matcher(target);
boolean matches = matcher.matches();
if (matches)
return apply(target,request,response, matcher);
return null;
}
/* ------------------------------------------------------------ */
/**
* Apply this rule to the request/response pair.
* Called by {@link #matchAndApply(String, HttpServletRequest, HttpServletResponse)} if the regex matches.
* @param target field to attempt match
* @param request request object
* @param response response object
* @param matcher The Regex matcher that matched the request (with capture groups available for replacement).
* @return The target (possible updated).
* @throws IOException exceptions dealing with operating on request or response objects
*/
protected abstract String apply(String target, HttpServletRequest request, HttpServletResponse response, Matcher matcher) throws IOException;
/* ------------------------------------------------------------ */
/**
* Returns the regular expression string.
*/
public String toString()
{
return super.toString()+"["+_regex+"]";
}
}