// Copyright 2004, 2005 The Apache Software Foundation
//
// Licensed 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.
package org.apache.tapestry.link;
import org.apache.tapestry.IAction;
import org.apache.tapestry.IActionListener;
import org.apache.tapestry.IBinding;
import org.apache.tapestry.IRequestCycle;
import org.apache.tapestry.RenderRewoundException;
import org.apache.tapestry.Tapestry;
import org.apache.tapestry.engine.ActionServiceParameter;
import org.apache.tapestry.engine.ILink;
import org.apache.tapestry.listener.ListenerInvoker;
/**
* A component for creating a link that is handled using the action service. [ <a
* href="../../../../../ComponentReference/ActionLink.html">Component Reference </a>]
*
* @author Howard Lewis Ship
*/
public abstract class ActionLink extends AbstractLinkComponent implements IAction
{
public abstract boolean isStateful();
/**
* Returns true if the stateful parameter is bound to a true value. If stateful is not bound,
* also returns the default, true.
* <p>
* Note that this method can be called when the component is not rendering, therefore it must
* directly access the {@link IBinding}for the stateful parameter.
*/
public boolean getRequiresSession()
{
return isStateful();
}
public ILink getLink(IRequestCycle cycle)
{
String actionId = cycle.getNextActionId();
if (cycle.isRewound(this))
{
getListenerInvoker().invokeListener(getListener(), this, cycle);
throw new RenderRewoundException(this);
}
return getLink(cycle, Tapestry.ACTION_SERVICE, new ActionServiceParameter(this, actionId));
}
public abstract IActionListener getListener();
public abstract ListenerInvoker getListenerInvoker();
}