    001// Copyright 2008 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007//     http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.internal.services;
    016
    017import org.apache.tapestry5.http.services.HttpServletRequestFilter;
    018import org.apache.tapestry5.http.services.HttpServletRequestHandler;
    019
    020import javax.servlet.http.HttpServletRequest;
    021import javax.servlet.http.HttpServletResponse;
    022import java.io.IOException;
    023import java.util.Collection;
    024import java.util.regex.Pattern;
    025
    026public class IgnoredPathsFilter implements HttpServletRequestFilter
    027{
    028    private final Pattern[] ignoredPatterns;
    029
    030    // if there are no ignore patterns, just pass every request to the next item in the pipeline
    031    private final boolean passThrough;
    032
    033    public IgnoredPathsFilter(Collection<String> configuration)
    034    {
    035        ignoredPatterns = new Pattern[configuration.size()];
    036
    037        int i = 0;
    038
    039        for (String regexp : configuration)
    040        {
    041            Pattern p = Pattern.compile(regexp, Pattern.CASE_INSENSITIVE);
    042
    043            ignoredPatterns[i++] = p;
    044        }
    045        passThrough = ignoredPatterns.length == 0;
    046    }
    047
    048    public boolean service(HttpServletRequest request, HttpServletResponse response, HttpServletRequestHandler handler)
    049            throws IOException
    050    {
    051        // The servlet path should be "/", and path info is everything after that.
    052
    053        if (!passThrough)
    054        {
    055            String path = request.getServletPath();
    056            String pathInfo = request.getPathInfo();
    057
    058            if (pathInfo != null) path += pathInfo;
    059
    060
    061            for (Pattern p : ignoredPatterns)
    062            {
    063                if (p.matcher(path).matches()) return false;
    064            }
    065        }
    066
    067        // Not a match, so let it go.
    068
    069        return handler.service(request, response);
    070    }
    071}