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 015package org.apache.tapestry.engine; 016 017import java.util.Locale; 018 019import org.apache.tapestry.IComponent; 020import org.apache.tapestry.IRequestCycle; 021import org.apache.tapestry.parse.ComponentTemplate; 022 023/** 024 * Acts as a delegate to the {@link org.apache.tapestry.services.TemplateSource}, 025 * providing access to page and component templates after the normal search mechanisms have failed. 026 * 027 * <p> 028 * The delegate must be threadsafe. 029 * 030 * @author Howard Lewis Ship 031 * @since 3.0 032 * @see org.apache.tapestry.services.impl.TemplateSourceImpl 033 * 034 **/ 035 036public interface ITemplateSourceDelegate 037{ 038 /** 039 * Invoked by the {@link ITemplateSource} when a template can't be found 040 * by normal means (i.e., in the normal locations). This method 041 * should find the template. The result may be null. The delegate 042 * is responsible for caching the result. 043 * 044 * @param cycle for access to Tapestry and Servlet API objects 045 * @param component component (or page) for which a template is needed 046 * @param locale the desired locale for the template 047 * 048 **/ 049 050 public ComponentTemplate findTemplate(IRequestCycle cycle, IComponent component, Locale locale); 051}