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.http.services;
014
015import java.io.IOException;
016
017import javax.servlet.http.HttpServletRequest;
018import javax.servlet.http.HttpServletResponse;
019
020import org.apache.tapestry5.http.CorsHandlerResult;
021
022/**
023 * Interface implemented by classes handling CORS (Cross-Origin Resource Sharing) in requests.
024 * Implementations should be contributed to {@link CorsHttpServletRequestFilter} and 
025 * can use the useful methods from {@link CorsHandlerHelper}.
026 * @see CorsHandlerHelper
027 * @see CorsHandlerResult
028 * @see CorsHttpServletRequestFilter
029 * @since 5.8.2
030 */
031public interface CorsHandler
032{
033    /**
034     * Handles the CORS processing of a request, possibly doing nothing. This method
035     * cannot return <code>null</code>.
036     * @return a {@linkplain CorsHandlerResult} object. 
037     */
038    CorsHandlerResult handle(HttpServletRequest request, HttpServletResponse response) throws IOException;
039}