001    // Copyright 2010 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.tapestry5.annotations;
016    
017    import static java.lang.annotation.ElementType.METHOD;
018    import static java.lang.annotation.RetentionPolicy.RUNTIME;
019    import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.COMPONENT;
020    import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.MIXIN;
021    import static org.apache.tapestry5.ioc.annotations.AnnotationUseContext.PAGE;
022    
023    import java.lang.annotation.Documented;
024    import java.lang.annotation.Retention;
025    import java.lang.annotation.Target;
026    
027    import org.apache.tapestry5.corelib.components.Grid;
028    import org.apache.tapestry5.internal.transform.PageResetAnnotationWorker;
029    import org.apache.tapestry5.ioc.annotations.UseWith;
030    
031    /**
032     * Marker annotation for a method that should be invoked when a page is reset. A page reset occurs
033     * when a page is linked to from another page. This is an opportunity to re-initialize aspects of a
034     * page when the user returns to a page after visiting other pages. A common example is to
035     * reset the active page of a {@link Grid} component.
036     * <p>
037     * Methods marked with this annotation are invoked <em>after</em> the page is sent the
038     * <code>activate</code> event. This is to allow the page to reset itself as appropriate for
039     * whatever persistent state was encoded in its page activation context.
040     * 
041     * @since 5.2.0
042     * @see PageResetAnnotationWorker
043     */
044    @Target(METHOD)
045    @Retention(RUNTIME)
046    @Documented
047    @UseWith(
048    { COMPONENT, MIXIN, PAGE })
049    public @interface PageReset
050    {
051    }