001/*
002 * Copyright 2002-2015 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.web.cors;
018
019import javax.servlet.http.HttpServletRequest;
020
021import org.springframework.http.HttpHeaders;
022import org.springframework.http.HttpMethod;
023
024/**
025 * Utility class for CORS request handling based on the
026 * <a href="https://www.w3.org/TR/cors/">CORS W3C recommendation</a>.
027 *
028 * @author Sebastien Deleuze
029 * @since 4.2
030 */
031public abstract class CorsUtils {
032
033        /**
034         * Returns {@code true} if the request is a valid CORS one.
035         */
036        public static boolean isCorsRequest(HttpServletRequest request) {
037                return (request.getHeader(HttpHeaders.ORIGIN) != null);
038        }
039
040        /**
041         * Returns {@code true} if the request is a valid CORS pre-flight one.
042         */
043        public static boolean isPreFlightRequest(HttpServletRequest request) {
044                return (isCorsRequest(request) && HttpMethod.OPTIONS.matches(request.getMethod()) &&
045                                request.getHeader(HttpHeaders.ACCESS_CONTROL_REQUEST_METHOD) != null);
046        }
047
048}