001/* 002 * Copyright 2002-2017 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.lang.Nullable; 023import org.springframework.messaging.Message; 024import org.springframework.util.Assert; 025 026/** 027 * A base class for events for a message received from a WebSocket client and 028 * parsed into a higher-level sub-protocol (e.g. STOMP). 029 * 030 * @author Rossen Stoyanchev 031 * @since 4.1 032 */ 033@SuppressWarnings("serial") 034public abstract class AbstractSubProtocolEvent extends ApplicationEvent { 035 036 private final Message<byte[]> message; 037 038 @Nullable 039 private final Principal user; 040 041 042 /** 043 * Create a new AbstractSubProtocolEvent. 044 * @param source the component that published the event (never {@code null}) 045 * @param message the incoming message (never {@code null}) 046 */ 047 protected AbstractSubProtocolEvent(Object source, Message<byte[]> message) { 048 this(source, message, null); 049 } 050 051 /** 052 * Create a new AbstractSubProtocolEvent. 053 * @param source the component that published the event (never {@code null}) 054 * @param message the incoming message (never {@code null}) 055 */ 056 protected AbstractSubProtocolEvent(Object source, Message<byte[]> message, @Nullable Principal user) { 057 super(source); 058 Assert.notNull(message, "Message must not be null"); 059 this.message = message; 060 this.user = user; 061 } 062 063 064 /** 065 * Return the Message associated with the event. Here is an example of 066 * obtaining information about the session id or any headers in the 067 * message: 068 * <pre class="code"> 069 * StompHeaderAccessor headers = StompHeaderAccessor.wrap(message); 070 * headers.getSessionId(); 071 * headers.getSessionAttributes(); 072 * headers.getPrincipal(); 073 * </pre> 074 */ 075 public Message<byte[]> getMessage() { 076 return this.message; 077 } 078 079 /** 080 * Return the user for the session associated with the event. 081 */ 082 @Nullable 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}