    001    // Copyright 2007, 2008, 2009, 2011 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
    015    package org.apache.tapestry5.internal.services;
    016
    017    import org.apache.tapestry5.Link;
    018    import org.apache.tapestry5.services.*;
    019
    020    import java.util.Collection;
    021
    022    /**
    023     * Implements simple client-persistent properties. Most of the logic is delegated to an instance of {@link
    024     * ClientPersistentFieldStorage}. This division of layer allows this service to be a true singleton, and a listener to
    025     * the {@link LinkSource}, and allow per-request state to be isolated inside the other service.
    026     */
    027    public class ClientPersistentFieldStrategy implements PersistentFieldStrategy, LinkCreationListener2
    028    {
    029        private final ClientPersistentFieldStorage storage;
    030
    031        public ClientPersistentFieldStrategy(ClientPersistentFieldStorage storage)
    032        {
    033            this.storage = storage;
    034        }
    035
    036        public Collection<PersistentFieldChange> gatherFieldChanges(String pageName)
    037        {
    038            return storage.gatherFieldChanges(pageName);
    039        }
    040
    041        public void postChange(String pageName, String componentId, String fieldName, Object newValue)
    042        {
    043            storage.postChange(pageName, componentId, fieldName, newValue);
    044        }
    045
    046        public void createdComponentEventLink(Link link, ComponentEventRequestParameters parameters)
    047        {
    048            storage.updateLink(link);
    049        }
    050
    051        public void createdPageRenderLink(Link link, PageRenderRequestParameters parameters)
    052        {
    053            storage.updateLink(link);
    054        }
    055
    056        public void discardChanges(String pageName)
    057        {
    058            storage.discardChanges(pageName);
    059        }
    060    }