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.server.support; 018 019import java.util.Collections; 020import java.util.List; 021import java.util.Map; 022 023import org.apache.commons.logging.Log; 024import org.apache.commons.logging.LogFactory; 025 026import org.springframework.http.server.ServerHttpRequest; 027import org.springframework.http.server.ServerHttpResponse; 028import org.springframework.web.socket.WebSocketHandler; 029import org.springframework.web.socket.server.HandshakeInterceptor; 030 031/** 032 * A helper class that assists with invoking a list of handshake interceptors. 033 * 034 * @author Rossen Stoyanchev 035 * @since 4.0 036 */ 037public class HandshakeInterceptorChain { 038 039 private static final Log logger = LogFactory.getLog(HandshakeInterceptorChain.class); 040 041 private final List<HandshakeInterceptor> interceptors; 042 043 private final WebSocketHandler wsHandler; 044 045 private int interceptorIndex = -1; 046 047 048 public HandshakeInterceptorChain(List<HandshakeInterceptor> interceptors, WebSocketHandler wsHandler) { 049 this.interceptors = (interceptors != null ? interceptors : Collections.<HandshakeInterceptor>emptyList()); 050 this.wsHandler = wsHandler; 051 } 052 053 054 public boolean applyBeforeHandshake(ServerHttpRequest request, ServerHttpResponse response, 055 Map<String, Object> attributes) throws Exception { 056 057 for (int i = 0; i < this.interceptors.size(); i++) { 058 HandshakeInterceptor interceptor = this.interceptors.get(i); 059 if (!interceptor.beforeHandshake(request, response, this.wsHandler, attributes)) { 060 if (logger.isDebugEnabled()) { 061 logger.debug(interceptor + " returns false from beforeHandshake - precluding handshake"); 062 } 063 applyAfterHandshake(request, response, null); 064 return false; 065 } 066 this.interceptorIndex = i; 067 } 068 return true; 069 } 070 071 072 public void applyAfterHandshake(ServerHttpRequest request, ServerHttpResponse response, Exception failure) { 073 for (int i = this.interceptorIndex; i >= 0; i--) { 074 HandshakeInterceptor interceptor = this.interceptors.get(i); 075 try { 076 interceptor.afterHandshake(request, response, this.wsHandler, failure); 077 } 078 catch (Throwable ex) { 079 if (logger.isWarnEnabled()) { 080 logger.warn(interceptor + " threw exception in afterHandshake: " + ex); 081 } 082 } 083 } 084 } 085 086}