001    // Copyright May 20, 2006 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    package org.apache.tapestry;
015    
016    import org.apache.tapestry.event.BrowserEvent;
017    
018    /**
019     * Interface that defines classes that may be invoked directly by
020     * the event service. 
021     * 
022     * @author jkuhnert
023     */
024    public interface IDirectEvent extends IComponent
025    {
026    
027        /**
028         *  Invoked by the event service to have the component peform
029         *  the appropriate action. 
030         **/
031        
032        void triggerEvent(IRequestCycle cycle, BrowserEvent event);
033    
034        /**
035         *  Invoked by the event service to query the component as to
036         *  whether it is stateful.  If stateful and no 
037         *  {@link javax.servlet.http.HttpSession} is active, then a
038         *  {@link org.apache.tapestry.StaleSessionException} is
039         *  thrown by the service.
040         * 
041         **/
042    
043        boolean isStateful();
044    }