    001    // Copyright 2006, 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.UsesOrderedConfiguration;
    018
    019    import java.io.IOException;
    020
    021    /**
    022     * Handler interface for component event requests. Component event requests <em>do things</em> such as process a form
    023     * submission or otherwise change state. In the majority of cases, after the component event, a redirect response is
    024     * sent to the client which, in turn, causes a page render.
    025     * <p/>
    026     * The ComponentEventRequestHandler service is a pipeline, allowing extensibility via contributed {@linkplain
    027     * org.apache.tapestry5.services.ComponentEventRequestFilter filters}.    It may be distinguished by the @{@link
    028     * org.apache.tapestry5.services.Traditional} marker annotation.
    029     * <p/>
    030     * A second service, AjaxComponentEventRequestHandler is also a pipeline and may be distinguished by the @{@link
    031     * org.apache.tapestry5.services.Ajax} marker annotation.
    032     *
    033     * @see org.apache.tapestry5.corelib.components.ActionLink
    034     * @see org.apache.tapestry5.corelib.components.Form
    035     */
    036    @UsesOrderedConfiguration(ComponentEventRequestFilter.class)
    037    public interface ComponentEventRequestHandler
    038    {
    039        /**
    040         * Handler for a component action request which will trigger an event on a component and use the return value to
    041         * send a response to the client (typically, a redirect to a page render URL).
    042         *
    043         * @param parameters defining the requst
    044         */
    045        void handle(ComponentEventRequestParameters parameters) throws IOException;
    046    }