    001// Licensed under the Apache License, Version 2.0 (the "License");
    002// you may not use this file except in compliance with the License.
    003// You may obtain a copy of the License at
    004//
    005//     http://www.apache.org/licenses/LICENSE-2.0
    006//
    007// Unless required by applicable law or agreed to in writing, software
    008// distributed under the License is distributed on an "AS IS" BASIS,
    009// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    010// See the License for the specific language governing permissions and
    011// limitations under the License.
    012
    013package org.apache.tapestry5.services;
    014
    015import org.apache.tapestry5.ioc.annotations.UsesOrderedConfiguration;
    016
    017import java.io.IOException;
    018
    019/**
    020 * Handler interface for component event requests. Component event requests <em>do things</em> such as process a form
    021 * submission or otherwise change state. In the majority of cases, after the component event, a redirect response is
    022 * sent to the client which, in turn, causes a page render.
    023 *
    024 * The ComponentEventRequestHandler service is a pipeline, allowing extensibility via contributed {@linkplain
    025 * org.apache.tapestry5.services.ComponentEventRequestFilter filters}.    It may be distinguished by the @{@link
    026 * org.apache.tapestry5.services.Traditional} marker annotation.
    027 *
    028 * A second service, AjaxComponentEventRequestHandler is also a pipeline and may be distinguished by the @{@link
    029 * org.apache.tapestry5.services.Ajax} marker annotation.
    030 *
    031 * @see org.apache.tapestry5.corelib.components.ActionLink
    032 * @see org.apache.tapestry5.corelib.components.Form
    033 */
    034@UsesOrderedConfiguration(ComponentEventRequestFilter.class)
    035public interface ComponentEventRequestHandler
    036{
    037    /**
    038     * Handler for a component action request which will trigger an event on a component and use the return value to
    039     * send a response to the client (typically, a redirect to a page render URL).
    040     *
    041     * @param parameters defining the requst
    042     */
    043    void handle(ComponentEventRequestParameters parameters) throws IOException;
    044}