001/* 002 * Copyright 2002-2016 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.session; 018 019import java.io.IOException; 020import java.util.Map; 021 022import org.springframework.http.server.ServerHttpRequest; 023import org.springframework.http.server.ServerHttpResponse; 024import org.springframework.web.socket.WebSocketHandler; 025import org.springframework.web.socket.sockjs.SockJsTransportFailureException; 026import org.springframework.web.socket.sockjs.frame.SockJsFrame; 027import org.springframework.web.socket.sockjs.frame.SockJsMessageCodec; 028import org.springframework.web.socket.sockjs.transport.SockJsServiceConfig; 029 030/** 031 * A SockJS session for use with polling HTTP transports. 032 * 033 * @author Rossen Stoyanchev 034 * @since 4.0 035 */ 036public class PollingSockJsSession extends AbstractHttpSockJsSession { 037 038 public PollingSockJsSession(String sessionId, SockJsServiceConfig config, 039 WebSocketHandler wsHandler, Map<String, Object> attributes) { 040 041 super(sessionId, config, wsHandler, attributes); 042 } 043 044 045 @Override 046 protected void handleRequestInternal(ServerHttpRequest request, ServerHttpResponse response, 047 boolean initialRequest) throws IOException { 048 049 if (initialRequest) { 050 writeFrame(SockJsFrame.openFrame()); 051 } 052 else if (!getMessageCache().isEmpty()) { 053 flushCache(); 054 } 055 else { 056 scheduleHeartbeat(); 057 } 058 } 059 060 @Override 061 protected void flushCache() throws SockJsTransportFailureException { 062 String[] messages = new String[getMessageCache().size()]; 063 for (int i = 0; i < messages.length; i++) { 064 messages[i] = getMessageCache().poll(); 065 } 066 SockJsMessageCodec messageCodec = getSockJsServiceConfig().getMessageCodec(); 067 SockJsFrame frame = SockJsFrame.messageFrame(messageCodec, messages); 068 writeFrame(frame); 069 } 070 071 @Override 072 protected void writeFrame(SockJsFrame frame) throws SockJsTransportFailureException { 073 super.writeFrame(frame); 074 resetRequest(); 075 } 076 077}