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; 016 017 /** 018 * Interface that defines classes that may be messaged by the direct 019 * service. 020 * 021 * @author Howard Lewis Ship 022 **/ 023 024 public interface IDirect extends IComponent 025 { 026 /** 027 * Invoked by the direct service to have the component peform 028 * the appropriate action. The {@link org.apache.tapestry.link.DirectLink} component will 029 * notify its listener. 030 * 031 **/ 032 033 public void trigger(IRequestCycle cycle); 034 035 /** 036 * Invoked by the direct service to query the component as to 037 * whether it is stateful. If stateful and no 038 * {@link javax.servlet.http.HttpSession} is active, then a 039 * {@link org.apache.tapestry.StaleSessionException} is 040 * thrown by the service. 041 * 042 * @since 2.3 043 * 044 **/ 045 046 public boolean isStateful(); 047 048 }