001/* 002 * Copyright 2002-2019 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.sockjs.transport.handler; 018 019import java.nio.charset.StandardCharsets; 020import java.util.Map; 021 022import org.springframework.http.MediaType; 023import org.springframework.http.server.ServerHttpRequest; 024import org.springframework.web.socket.WebSocketHandler; 025import org.springframework.web.socket.sockjs.frame.DefaultSockJsFrameFormat; 026import org.springframework.web.socket.sockjs.frame.SockJsFrameFormat; 027import org.springframework.web.socket.sockjs.transport.SockJsSession; 028import org.springframework.web.socket.sockjs.transport.TransportHandler; 029import org.springframework.web.socket.sockjs.transport.TransportType; 030import org.springframework.web.socket.sockjs.transport.session.PollingSockJsSession; 031 032/** 033 * A {@link TransportHandler} based on XHR (long) polling. 034 * 035 * @author Rossen Stoyanchev 036 * @since 4.0 037 */ 038public class XhrPollingTransportHandler extends AbstractHttpSendingTransportHandler { 039 040 @Override 041 public TransportType getTransportType() { 042 return TransportType.XHR; 043 } 044 045 @Override 046 protected MediaType getContentType() { 047 return new MediaType("application", "javascript", StandardCharsets.UTF_8); 048 } 049 050 @Override 051 protected SockJsFrameFormat getFrameFormat(ServerHttpRequest request) { 052 return new DefaultSockJsFrameFormat("%s\n"); 053 } 054 055 @Override 056 public boolean checkSessionType(SockJsSession session) { 057 return (session instanceof PollingSockJsSession); 058 } 059 060 @Override 061 public PollingSockJsSession createSession( 062 String sessionId, WebSocketHandler handler, Map<String, Object> attributes) { 063 064 return new PollingSockJsSession(sessionId, getServiceConfig(), handler, attributes); 065 } 066 067}