    001    // Copyright 2007, 2008 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.services;
    016
    017    import org.apache.tapestry5.ioc.annotations.UsesMappedConfiguration;
    018
    019    import java.io.IOException;
    020
    021    /**
    022     * Responsible for handling the return value provided by a component event handler method.
    023     * <p/>
    024     * There are two services built into Tapestry that implement this interface: ComponentEventResultProcessor (used for
    025     * ordinary page-oriented requests, and distinguished by the @{@link org.apache.tapestry5.services.Traditional}
    026     * and/or @{@link org.apache.tapestry5.ioc.annotations.Primary} marker annotations) and
    027     * AjaxComponentEventResultProcessor, used
    028     * for Ajax requests (which typically return a partially rendered page), distinguished by the @{@link
    029     * org.apache.tapestry5.services.Ajax} marker annotation.
    030     * @param <T>
    031     */
    032    @UsesMappedConfiguration(key = Class.class, value = ComponentEventResultProcessor.class)
    033    public interface ComponentEventResultProcessor<T>
    034    {
    035        /**
    036         * For a given, non-null return value from a component event method, construct and send a response.
    037         *
    038         * @param value the value returned from a method
    039         * @throws RuntimeException if the value can not handled
    040         */
    041        void processResultValue(T value) throws IOException;
    042    }