001/* 002 * Copyright 2002-2018 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; 018 019/** 020 * A message that can be handled or sent on a WebSocket connection. 021 * 022 * @author Rossen Stoyanchev 023 * @since 4.0 024 * @param <T> the payload type 025 */ 026public interface WebSocketMessage<T> { 027 028 /** 029 * Return the message payload (never {@code null}). 030 */ 031 T getPayload(); 032 033 /** 034 * Return the number of bytes contained in the message. 035 */ 036 int getPayloadLength(); 037 038 /** 039 * When partial message support is available and requested via 040 * {@link org.springframework.web.socket.WebSocketHandler#supportsPartialMessages()}, 041 * this method returns {@code true} if the current message is the last part of the 042 * complete WebSocket message sent by the client. Otherwise {@code false} is returned 043 * if partial message support is either not available or not enabled. 044 */ 045 boolean isLast(); 046 047}