    001// Copyright 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
    015package org.apache.tapestry5;
    016
    017import java.io.Serializable;
    018
    019/**
    020 * An action that is associated with a component. This is used in several areas of Tapestry and is primarily an attempt
    021 * to externalize state for a component so that it can be recorded outside the object.
    022 * <p/>
    023 * ComponentActions should be immutable. They are often created during one request and associated with a particular
    024 * component instance. They are then used in a later request (with an equivalent component instance).
    025 * <p/>
    026 * ComponentActions are serializable (they are often serialized into Base64 strings for storage on the client).
    027 */
    028public interface ComponentAction<T> extends Serializable
    029{
    030    /**
    031     * Passed a component instance, the action should operate upon the instance.
    032     */
    033    void execute(T component);
    034}