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    
015    package org.apache.tapestry.link;
016    
017    import org.apache.tapestry.IAction;
018    import org.apache.tapestry.IActionListener;
019    import org.apache.tapestry.IRequestCycle;
020    import org.apache.tapestry.RenderRewoundException;
021    import org.apache.tapestry.Tapestry;
022    import org.apache.tapestry.engine.ActionServiceParameter;
023    import org.apache.tapestry.engine.ILink;
024    import org.apache.tapestry.listener.ListenerInvoker;
025    
026    /**
027     * A component for creating a link that is handled using the action service. [ <a
028     * href="../../../../../ComponentReference/ActionLink.html">Component Reference </a>]
029     * 
030     * @author Howard Lewis Ship
031     * @deprecated To be removed in 4.1
032     */
033    
034    public abstract class ActionLink extends AbstractLinkComponent implements IAction
035    {
036        public abstract boolean isStateful();
037    
038        /**
039         * Returns true if the stateful parameter is bound to a true value. If stateful is not bound,
040         * also returns the default, true.
041         * <p>
042         * Note that this method can be called when the component is not rendering, therefore it must
043         * directly access the {@link IBinding}for the stateful parameter.
044         */
045    
046        public boolean getRequiresSession()
047        {
048            return isStateful();
049        }
050    
051        public ILink getLink(IRequestCycle cycle)
052        {
053            String actionId = cycle.getNextActionId();
054    
055            if (cycle.isRewound(this))
056            {
057                getListenerInvoker().invokeListener(getListener(), this, cycle);
058    
059                throw new RenderRewoundException(this);
060            }
061    
062            return getLink(cycle, Tapestry.ACTION_SERVICE, new ActionServiceParameter(this, actionId));
063        }
064    
065        public abstract IActionListener getListener();
066    
067        public abstract ListenerInvoker getListenerInvoker();
068    }