001/*
002 * Copyright 2002-2014 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.socket.messaging;
018
019import java.security.Principal;
020
021import org.springframework.context.ApplicationEvent;
022import org.springframework.messaging.Message;
023import org.springframework.util.Assert;
024
025/**
026 * A base class for events for a message received from a WebSocket client and
027 * parsed into a higher-level sub-protocol (e.g. STOMP).
028 *
029 * @author Rossen Stoyanchev
030 * @since 4.1
031 */
032@SuppressWarnings("serial")
033public abstract class AbstractSubProtocolEvent extends ApplicationEvent {
034
035        private final Message<byte[]> message;
036
037        private final Principal user;
038
039
040        /**
041         * Create a new AbstractSubProtocolEvent.
042         * @param source the component that published the event (never {@code null})
043         * @param message the incoming message
044         */
045        protected AbstractSubProtocolEvent(Object source, Message<byte[]> message) {
046                super(source);
047                Assert.notNull(message, "Message must not be null");
048                this.message = message;
049                this.user = null;
050        }
051
052        /**
053         * Create a new AbstractSubProtocolEvent.
054         * @param source the component that published the event (never {@code null})
055         * @param message the incoming message
056         */
057        protected AbstractSubProtocolEvent(Object source, Message<byte[]> message, Principal user) {
058                super(source);
059                Assert.notNull(message, "Message must not be null");
060                this.message = message;
061                this.user = user;
062        }
063
064
065        /**
066         * Return the Message associated with the event. Here is an example of
067         * obtaining information about the session id or any headers in the
068         * message:
069         * <pre class="code">
070         * StompHeaderAccessor headers = StompHeaderAccessor.wrap(message);
071         * headers.getSessionId();
072         * headers.getSessionAttributes();
073         * headers.getPrincipal();
074         * </pre>
075         */
076        public Message<byte[]> getMessage() {
077                return this.message;
078        }
079
080        /**
081         * Return the user for the session associated with the event.
082         */
083        public Principal getUser() {
084                return this.user;
085        }
086
087        @Override
088        public String toString() {
089                return getClass().getSimpleName() + "[" + this.message + "]";
090        }
091
092}