    001    // Copyright 2007 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.internal.services;
    016
    017    import org.apache.tapestry5.ComponentResources;
    018
    019    /**
    020     * A kind of callback that can easily be injected into a transformed class to perform complex work.
    021     * <p/>
    022     * These callbacks are often injected into a transformed component class via {@link
    023     * org.apache.tapestry5.services.ClassTransformation#addInjectedField(Class, String, Object)}. Bear in mind that such
    024     * callbacks must be <em>threadsafe</em>, since every instance of such a class will share a single instance of the
    025     * operation.
    026     */
    027    public interface ComponentResourcesOperation
    028    {
    029        /**
    030         * Perform some operation that requires the components' resources.
    031         */
    032        void perform(ComponentResources resources);
    033    }