001// Copyright 2006, 2007, 2009 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.tapestry5.annotations;
016
017import java.lang.annotation.Documented;
018import java.lang.annotation.ElementType;
019import java.lang.annotation.Retention;
020import static java.lang.annotation.RetentionPolicy.RUNTIME;
021import java.lang.annotation.Target;
022
023import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.*;
024import org.apache.tapestry5.ioc.annotations.UseWith;
025
026/**
027 * Marker annotation for methods that should be executed at the start of rendering the component. This usually includes
028 * rendering of the component's start tag.
029 * <p/>
030 * Such methods may optionally take a {@link org.apache.tapestry5.MarkupWriter} parameter, and may return void or
031 * boolean. Returning true or void will allow the component to advance into the render template / render body phase. If
032 * a body is present, the {@link org.apache.tapestry5.annotations.BeforeRenderBody} phase will execute. If a component
033 * has a template, the {@link BeforeRenderTemplate} phase will execute (and the render body will only occur if the
034 * template directs so).
035 * <p/>
036 * Either way, the {@link org.apache.tapestry5.annotations.AfterRender} phase will execute after the template and/or
037 * body have rendered. A component with a body but without a template will still see the {@link
038 * org.apache.tapestry5.annotations.BeforeRenderBody} phase execute.
039 * <p/>
040 * Returning false will skip rendering of the template and/or body, and jump directly to the {@link AfterRender} phase.
041 */
042@Target(ElementType.METHOD)
043@Retention(RUNTIME)
044@Documented
045@UseWith({COMPONENT,MIXIN,PAGE})
046public @interface BeginRender
047{
048
049}