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.client.standard;
018
019import java.util.Arrays;
020import java.util.List;
021
022import javax.websocket.ClientEndpointConfig;
023import javax.websocket.ClientEndpointConfig.Configurator;
024import javax.websocket.ContainerProvider;
025import javax.websocket.Decoder;
026import javax.websocket.Encoder;
027import javax.websocket.Endpoint;
028import javax.websocket.Extension;
029import javax.websocket.Session;
030import javax.websocket.WebSocketContainer;
031
032import org.springframework.beans.factory.BeanFactory;
033import org.springframework.beans.factory.BeanFactoryAware;
034import org.springframework.core.task.SimpleAsyncTaskExecutor;
035import org.springframework.core.task.TaskExecutor;
036import org.springframework.lang.Nullable;
037import org.springframework.util.Assert;
038import org.springframework.web.socket.client.ConnectionManagerSupport;
039import org.springframework.web.socket.handler.BeanCreatingHandlerProvider;
040
041/**
042 * A WebSocket connection manager that is given a URI, an {@link Endpoint}, connects to a
043 * WebSocket server through the {@link #start()} and {@link #stop()} methods. If
044 * {@link #setAutoStartup(boolean)} is set to {@code true} this will be done automatically
045 * when the Spring ApplicationContext is refreshed.
046 *
047 * @author Rossen Stoyanchev
048 * @since 4.0
049 * @see AnnotatedEndpointConnectionManager
050 */
051public class EndpointConnectionManager extends ConnectionManagerSupport implements BeanFactoryAware {
052
053        @Nullable
054        private final Endpoint endpoint;
055
056        @Nullable
057        private final BeanCreatingHandlerProvider<Endpoint> endpointProvider;
058
059        private final ClientEndpointConfig.Builder configBuilder = ClientEndpointConfig.Builder.create();
060
061        private WebSocketContainer webSocketContainer = ContainerProvider.getWebSocketContainer();
062
063        private TaskExecutor taskExecutor = new SimpleAsyncTaskExecutor("EndpointConnectionManager-");
064
065        @Nullable
066        private volatile Session session;
067
068
069        public EndpointConnectionManager(Endpoint endpoint, String uriTemplate, Object... uriVariables) {
070                super(uriTemplate, uriVariables);
071                Assert.notNull(endpoint, "endpoint must not be null");
072                this.endpoint = endpoint;
073                this.endpointProvider = null;
074        }
075
076        public EndpointConnectionManager(Class<? extends Endpoint> endpointClass, String uriTemplate, Object... uriVars) {
077                super(uriTemplate, uriVars);
078                Assert.notNull(endpointClass, "endpointClass must not be null");
079                this.endpoint = null;
080                this.endpointProvider = new BeanCreatingHandlerProvider<>(endpointClass);
081        }
082
083
084        public void setSupportedProtocols(String... protocols) {
085                this.configBuilder.preferredSubprotocols(Arrays.asList(protocols));
086        }
087
088        public void setExtensions(Extension... extensions) {
089                this.configBuilder.extensions(Arrays.asList(extensions));
090        }
091
092        public void setEncoders(List<Class<? extends Encoder>> encoders) {
093                this.configBuilder.encoders(encoders);
094        }
095
096        public void setDecoders(List<Class<? extends Decoder>> decoders) {
097                this.configBuilder.decoders(decoders);
098        }
099
100        public void setConfigurator(Configurator configurator) {
101                this.configBuilder.configurator(configurator);
102        }
103
104        public void setWebSocketContainer(WebSocketContainer webSocketContainer) {
105                this.webSocketContainer = webSocketContainer;
106        }
107
108        public WebSocketContainer getWebSocketContainer() {
109                return this.webSocketContainer;
110        }
111
112        @Override
113        public void setBeanFactory(BeanFactory beanFactory) {
114                if (this.endpointProvider != null) {
115                        this.endpointProvider.setBeanFactory(beanFactory);
116                }
117        }
118
119        /**
120         * Set a {@link TaskExecutor} to use to open connections.
121         * By default {@link SimpleAsyncTaskExecutor} is used.
122         */
123        public void setTaskExecutor(TaskExecutor taskExecutor) {
124                Assert.notNull(taskExecutor, "TaskExecutor must not be null");
125                this.taskExecutor = taskExecutor;
126        }
127
128        /**
129         * Return the configured {@link TaskExecutor}.
130         */
131        public TaskExecutor getTaskExecutor() {
132                return this.taskExecutor;
133        }
134
135
136        @Override
137        protected void openConnection() {
138                this.taskExecutor.execute(() -> {
139                        try {
140                                if (logger.isInfoEnabled()) {
141                                        logger.info("Connecting to WebSocket at " + getUri());
142                                }
143                                Endpoint endpointToUse = this.endpoint;
144                                if (endpointToUse == null) {
145                                        Assert.state(this.endpointProvider != null, "No endpoint set");
146                                        endpointToUse = this.endpointProvider.getHandler();
147                                }
148                                ClientEndpointConfig endpointConfig = this.configBuilder.build();
149                                this.session = getWebSocketContainer().connectToServer(endpointToUse, endpointConfig, getUri());
150                                logger.info("Successfully connected to WebSocket");
151                        }
152                        catch (Throwable ex) {
153                                logger.error("Failed to connect to WebSocket", ex);
154                        }
155                });
156        }
157
158        @Override
159        protected void closeConnection() throws Exception {
160                try {
161                        Session session = this.session;
162                        if (session != null && session.isOpen()) {
163                                session.close();
164                        }
165                }
166                finally {
167                        this.session = null;
168                }
169        }
170
171        @Override
172        protected boolean isConnected() {
173                Session session = this.session;
174                return (session != null && session.isOpen());
175        }
176
177}