/*
 * $Header$
 * $Revision:400312 $
 * $Date:2006-05-06 14:49:41 +0200 (Sat, 06 May 2006) $
 *
 * ====================================================================
 *
 *  Licensed to the Apache Software Foundation (ASF) under one or more
 *  contributor license agreements.  See the NOTICE file distributed with
 *  this work for additional information regarding copyright ownership.
 *  The ASF licenses this file to You 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package org.apache.commons.httpclient.cookie;

import java.util.Comparator;

import org.apache.commons.httpclient.Cookie;

This cookie comparator ensures that multiple cookies satisfying 
a common criteria are ordered in the Cookie header such
that those with more specific Path attributes precede those with
less specific.
 

This comparator assumes that Path attributes of two cookies 
path-match a commmon request-URI. Otherwise, the result of the
comparison is undefined.

Author:
Oleg Kalnichevski
Since:
3.1/**
 * This cookie comparator ensures that multiple cookies satisfying 
 * a common criteria are ordered in the <tt>Cookie</tt> header such
 * that those with more specific Path attributes precede those with
 * less specific.
 *  
 * <p>
 * This comparator assumes that Path attributes of two cookies 
 * path-match a commmon request-URI. Otherwise, the result of the
 * comparison is undefined.
 * </p>
 * 
 * @author <a href="mailto:oleg at ural.ru">Oleg Kalnichevski</a>
 * 
 * @since 3.1
 */
public class CookiePathComparator implements Comparator {

    private String normalizePath(final Cookie cookie) {
        String path = cookie.getPath();
        if (path == null) {
            path = "/";
        }
        if (!path.endsWith("/")) {
            path = path + "/";
        }
        return path;
    }
    
    public int compare(final Object o1, final Object o2) {
        Cookie c1 = (Cookie) o1;
        Cookie c2 = (Cookie) o2;
        String path1 = normalizePath(c1);
        String path2 = normalizePath(c2);
        if (path1.equals(path2)) {
            return 0;
        } else if (path1.startsWith(path2)) {
            return -1;
        } else if (path2.startsWith(path1)) {
            return 1;
        } else {
            // Does not really matter
            return 0;
        }
    }

}