001// Copyright 2004, 2005 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.tapestry.services;
016
017/**
018 * Used by other services to obtain cookie values for the current request.
019 * 
020 * @author Howard Lewis Ship
021 * @since 4.0
022 */
023public interface CookieSource
024{
025    /**
026     * Returns the value of the first cookie whose name matches. Returns null if no such cookie
027     * exists. This method is only aware of cookies that are part of the incoming request; it does
028     * not know about additional cookies added since then (via
029     * {@link #writeCookieValue(String, String)}).
030     */
031    String readCookieValue(String name);
032
033    /**
034     * Creates or updates a cookie value. The value is stored using a max age (in seconds) defined
035     * by the symbol <code>org.apache.tapestry.default-cookie-max-age</code>. The factory default
036     * for this value is the equivalent of one week.
037     */
038
039    void writeCookieValue(String name, String value);
040
041    /**
042     * As with {@link #writeCookieValue(String, String)} but an explicit maximum age may be set.
043     * 
044     * @param name
045     *            the name of the cookie
046     * @param value
047     *            the value to be stored in the cookie
048     * @param maxAge
049     *            the maximum age, in seconds, to store the cookie
050     */
051
052    void writeCookieValue(String name, String value, int maxAge);
053
054    /**
055     * Removes a previously written cookie, by writing a new cookie with a maxAge of 0.
056     */
057
058    void removeCookieValue(String name);
059}