    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
    015    package org.apache.tapestry5;
    016
    017    import 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     */
    028    public 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    }