1 /* |
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2 * Copyright (c) 2015, 2016, Oracle and/or its affiliates. All rights reserved. |
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3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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4 * |
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5 * This code is free software; you can redistribute it and/or modify it |
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6 * under the terms of the GNU General Public License version 2 only, as |
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7 * published by the Free Software Foundation. Oracle designates this |
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8 * particular file as subject to the "Classpath" exception as provided |
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9 * by Oracle in the LICENSE file that accompanied this code. |
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10 * |
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11 * This code is distributed in the hope that it will be useful, but WITHOUT |
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12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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14 * version 2 for more details (a copy is included in the LICENSE file that |
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15 * accompanied this code). |
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16 * |
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17 * You should have received a copy of the GNU General Public License version |
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18 * 2 along with this work; if not, write to the Free Software Foundation, |
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19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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20 * |
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21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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22 * or visit www.oracle.com if you need additional information or have any |
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23 * questions. |
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24 */ |
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25 |
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26 package java.net.http; |
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27 |
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28 import java.io.IOException; |
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29 import java.net.ProtocolException; |
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30 import java.net.URI; |
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31 import java.nio.ByteBuffer; |
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32 import java.time.Duration; |
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33 import java.util.Map; |
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34 import java.util.Optional; |
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35 import java.util.concurrent.CompletableFuture; |
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36 import java.util.concurrent.CompletionStage; |
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37 |
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38 /** |
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39 * A WebSocket client conforming to RFC 6455. |
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40 * |
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41 * <p> A {@code WebSocket} provides full-duplex communication over a TCP |
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42 * connection. |
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43 * |
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44 * <p> To create a {@code WebSocket} use a {@linkplain #newBuilder(URI, Listener) |
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45 * builder}. Once a {@code WebSocket} is obtained, it's ready to send and |
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46 * receive messages. When the {@code WebSocket} is no longer |
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47 * needed it must be closed: a Close message must both be {@linkplain |
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48 * #sendClose() sent} and {@linkplain Listener#onClose(WebSocket, Optional, |
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49 * String) received}. Otherwise, invoke {@link #abort() abort} to close abruptly. |
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50 * |
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51 * <p> Once closed the {@code WebSocket} remains closed and cannot be reopened. |
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52 * |
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53 * <p> Messages of type {@code X} are sent through the {@code WebSocket.sendX} |
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54 * methods and received through {@link WebSocket.Listener}{@code .onX} methods |
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55 * asynchronously. Each of the methods returns a {@link CompletionStage} which |
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56 * completes when the operation has completed. |
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57 * |
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58 * <p> Messages are received only if {@linkplain #request(long) requested}. |
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59 * |
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60 * <p> One outstanding send operation is permitted: if another send operation is |
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61 * initiated before the previous one has completed, an {@link |
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62 * IllegalStateException IllegalStateException} will be thrown. When sending, a |
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63 * message should not be modified until the returned {@code CompletableFuture} |
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64 * completes (either normally or exceptionally). |
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65 * |
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66 * <p> Messages can be sent and received as a whole or in parts. A whole message |
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67 * is a sequence of one or more messages in which the last message is marked |
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68 * when it is sent or received. |
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69 * |
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70 * <p> If the message is contained in a {@link ByteBuffer}, bytes are considered |
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71 * arranged from the {@code buffer}'s {@link ByteBuffer#position() position} to |
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72 * the {@code buffer}'s {@link ByteBuffer#limit() limit}. |
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73 * |
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74 * <p> Unless otherwise noted, passing a {@code null} argument to a constructor |
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75 * or method of this type will cause a {@link NullPointerException |
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76 * NullPointerException} to be thrown. |
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77 * |
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78 * @implNote The default implementation's methods do not block before returning |
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79 * a {@code CompletableFuture}. |
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80 * |
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81 * @since 9 |
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82 */ |
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83 public interface WebSocket { |
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84 |
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85 /** |
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86 * Creates a builder of {@code WebSocket}s connected to the given URI and |
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87 * receiving events with the given {@code Listener}. |
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88 * |
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89 * <p> Equivalent to: |
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90 * <pre>{@code |
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91 * WebSocket.newBuilder(uri, HttpClient.getDefault()) |
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92 * }</pre> |
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93 * |
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94 * @param uri |
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95 * the WebSocket URI as defined in the WebSocket Protocol |
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96 * (with "ws" or "wss" scheme) |
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97 * |
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98 * @param listener |
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99 * the listener |
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100 * |
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101 * @throws IllegalArgumentException |
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102 * if the {@code uri} is not a WebSocket URI |
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103 * @throws SecurityException |
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104 * if running under a security manager and the caller does |
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105 * not have permission to access the |
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106 * {@linkplain HttpClient#getDefault() default HttpClient} |
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107 * |
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108 * @return a builder |
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109 */ |
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110 static Builder newBuilder(URI uri, Listener listener) { |
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111 return newBuilder(uri, HttpClient.getDefault(), listener); |
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112 } |
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113 |
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114 /** |
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115 * Creates a builder of {@code WebSocket}s connected to the given URI and |
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116 * receiving events with the given {@code Listener}. |
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117 * |
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118 * <p> Providing a custom {@code client} allows for finer control over the |
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119 * opening handshake. |
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120 * |
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121 * <p> <b>Example</b> |
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122 * <pre>{@code |
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123 * HttpClient client = HttpClient.create() |
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124 * .proxy(ProxySelector.of(new InetSocketAddress("proxy.example.com", 80))) |
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125 * .build(); |
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126 * ... |
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127 * WebSocket.newBuilder(URI.create("ws://websocket.example.com"), client, listener)... |
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128 * }</pre> |
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129 * |
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130 * @param uri |
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131 * the WebSocket URI as defined in the WebSocket Protocol |
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132 * (with "ws" or "wss" scheme) |
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133 * |
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134 * @param client |
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135 * the HttpClient |
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136 * @param listener |
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137 * the listener |
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138 * |
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139 * @throws IllegalArgumentException |
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140 * if the uri is not a WebSocket URI |
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141 * |
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142 * @return a builder |
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143 */ |
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144 static Builder newBuilder(URI uri, HttpClient client, Listener listener) { |
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145 return new WSBuilder(uri, client, listener); |
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146 } |
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147 |
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148 /** |
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149 * A builder for creating {@code WebSocket} instances. |
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150 * |
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151 * <p> To build a {@code WebSocket}, instantiate a builder, configure it |
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152 * as required by calling intermediate methods (the ones that return the |
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153 * builder itself), then finally call {@link #buildAsync()} to get a {@link |
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154 * CompletableFuture} with resulting {@code WebSocket}. |
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155 * |
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156 * <p> If an intermediate method has not been called, an appropriate |
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157 * default value (or behavior) will be used. Unless otherwise noted, a |
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158 * repeated call to an intermediate method overwrites the previous value (or |
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159 * overrides the previous behaviour), if no exception is thrown. |
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160 * |
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161 * <p> Instances of {@code Builder} may not be safe for use by multiple |
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162 * threads. |
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163 * |
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164 * @since 9 |
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165 */ |
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166 interface Builder { |
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167 |
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168 /** |
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169 * Adds the given name-value pair to the list of additional headers for |
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170 * the opening handshake. |
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171 * |
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172 * <p> Headers defined in WebSocket Protocol are not allowed to be added. |
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173 * |
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174 * @param name |
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175 * the header name |
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176 * @param value |
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177 * the header value |
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178 * |
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179 * @return this builder |
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180 * |
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181 * @throws IllegalArgumentException |
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182 * if the {@code name} is a WebSocket defined header name |
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183 */ |
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184 Builder header(String name, String value); |
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185 |
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186 /** |
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187 * Includes a request for the given subprotocols during the opening |
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188 * handshake. |
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189 * |
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190 * <p> Among the requested subprotocols at most one will be chosen by |
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191 * the server. When the {@code WebSocket} is connected, the subprotocol |
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192 * in use is available from {@link WebSocket#getSubprotocol}. |
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193 * Subprotocols may be specified in the order of preference. |
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194 * |
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195 * <p> Each of the given subprotocols must conform to the relevant |
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196 * rules defined in the WebSocket Protocol. |
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197 * |
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198 * @param mostPreferred |
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199 * the most preferred subprotocol |
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200 * @param lesserPreferred |
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201 * the lesser preferred subprotocols, with the least preferred |
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202 * at the end |
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203 * |
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204 * @return this builder |
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205 * |
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206 * @throws IllegalArgumentException |
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207 * if any of the WebSocket Protocol rules relevant to |
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208 * subprotocols are violated |
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209 */ |
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210 Builder subprotocols(String mostPreferred, String... lesserPreferred); |
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211 |
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212 /** |
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213 * Sets a timeout for the opening handshake. |
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214 * |
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215 * <p> If the opening handshake is not finished within the specified |
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216 * amount of time then {@link #buildAsync()} completes exceptionally |
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217 * with a {@code HttpTimeoutException}. |
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218 * |
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219 * <p> If this method is not invoked then the timeout is deemed infinite. |
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220 * |
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221 * @param timeout |
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222 * the timeout |
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223 * |
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224 * @return this builder |
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225 */ |
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226 Builder connectTimeout(Duration timeout); |
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227 |
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228 /** |
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229 * Builds a {@code WebSocket}. |
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230 * |
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231 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
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232 * normally with the {@code WebSocket} when it is connected or completes |
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233 * exceptionally if an error occurs. |
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234 * |
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235 * <p> {@code CompletableFuture} may complete exceptionally with the |
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236 * following errors: |
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237 * <ul> |
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238 * <li> {@link IOException} |
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239 * if an I/O error occurs |
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240 * <li> {@link InterruptedException} |
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241 * if the operation was interrupted |
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242 * <li> {@link SecurityException} |
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243 * if a security manager is set, and the caller does not |
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244 * have a {@link java.net.URLPermission} for the WebSocket URI |
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245 * <li> {@link WebSocketHandshakeException} |
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246 * if the opening handshake fails |
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247 * </ul> |
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248 * |
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249 * @return a {@code CompletableFuture} with the {@code WebSocket} |
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250 */ |
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251 CompletableFuture<WebSocket> buildAsync(); |
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252 } |
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253 |
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254 /** |
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255 * A listener for events and messages on a {@code WebSocket}. |
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256 * |
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257 * <p> Each method below corresponds to a type of event. |
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258 * <ul> |
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259 * <li> {@link #onOpen onOpen} <br> |
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260 * This method is always the first to be invoked. |
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261 * <li> {@link #onText(WebSocket, CharSequence, WebSocket.MessagePart) |
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262 * onText}, {@link #onBinary(WebSocket, ByteBuffer, WebSocket.MessagePart) |
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263 * onBinary}, {@link #onPing(WebSocket, ByteBuffer) onPing} and {@link |
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264 * #onPong(WebSocket, ByteBuffer) onPong} <br> |
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265 * These methods are invoked zero or more times after {@code onOpen}. |
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266 * <li> {@link #onClose(WebSocket, Optional, String) onClose}, {@link |
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267 * #onError(WebSocket, Throwable) onError} <br> |
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268 * Only one of these methods is invoked, and that method is invoked last and |
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269 * at most once. |
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270 * </ul> |
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271 * |
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272 * <pre><code> |
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273 * onOpen (onText|onBinary|onPing|onPong)* (onClose|onError)? |
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274 * </code></pre> |
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275 * |
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276 * <p> Messages received by the {@code Listener} conform to the WebSocket |
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277 * Protocol, otherwise {@code onError} with a {@link ProtocolException} is |
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278 * invoked. |
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279 * |
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280 * <p> If a whole message is received, then the corresponding method |
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281 * ({@code onText} or {@code onBinary}) will be invoked with {@link |
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282 * WebSocket.MessagePart#WHOLE WHOLE} marker. Otherwise the method will be |
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283 * invoked with {@link WebSocket.MessagePart#FIRST FIRST}, zero or more |
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284 * times with {@link WebSocket.MessagePart#FIRST PART} and, finally, with |
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285 * {@link WebSocket.MessagePart#LAST LAST} markers. |
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286 * |
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287 * <pre><code> |
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288 * WHOLE|(FIRST PART* LAST) |
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289 * </code></pre> |
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290 * |
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291 * <p> All methods are invoked in a sequential (and |
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292 * <a href="../../../java/util/concurrent/package-summary.html#MemoryVisibility"> |
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293 * happens-before</a>) order, one after another, possibly by different |
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294 * threads. If any of the methods above throws an exception, {@code onError} |
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295 * is then invoked with that exception. Exceptions thrown from {@code |
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296 * onError} or {@code onClose} are ignored. |
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297 * |
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298 * <p> When the method returns, the message is deemed received. After this |
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299 * another messages may be received. |
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300 * |
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301 * <p> These invocations begin asynchronous processing which might not end |
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302 * with the invocation. To provide coordination, methods of {@code |
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303 * Listener} return a {@link CompletionStage CompletionStage}. The {@code |
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304 * CompletionStage} signals the {@code WebSocket} that the |
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305 * processing of a message has ended. For |
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306 * convenience, methods may return {@code null}, which means |
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307 * the same as returning an already completed {@code CompletionStage}. If |
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308 * the returned {@code CompletionStage} completes exceptionally, then {@link |
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309 * #onError(WebSocket, Throwable) onError} will be invoked with the |
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310 * exception. |
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311 * |
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312 * <p> Control of the message passes to the {@code Listener} with the |
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313 * invocation of the method. Control of the message returns to the {@code |
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314 * WebSocket} at the earliest of, either returning {@code null} from the |
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315 * method, or the completion of the {@code CompletionStage} returned from |
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316 * the method. The {@code WebSocket} does not access the message while it's |
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317 * not in its control. The {@code Listener} must not access the message |
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318 * after its control has been returned to the {@code WebSocket}. |
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319 * |
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320 * <p> It is the responsibility of the listener to make additional |
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321 * {@linkplain WebSocket#request(long) message requests}, when ready, so |
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322 * that messages are received eventually. |
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323 * |
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324 * <p> Methods above are never invoked with {@code null}s as their |
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325 * arguments. |
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326 * |
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327 * @since 9 |
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328 */ |
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329 interface Listener { |
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330 |
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331 /** |
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332 * Notifies the {@code Listener} that it is connected to the provided |
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333 * {@code WebSocket}. |
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334 * |
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335 * <p> The {@code onOpen} method does not correspond to any message |
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336 * from the WebSocket Protocol. It is a synthetic event. It is the first |
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337 * {@code Listener}'s method to be invoked. No other {@code Listener}'s |
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338 * methods are invoked before this one. The method is usually used to |
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339 * make an initial {@linkplain WebSocket#request(long) request} for |
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340 * messages. |
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341 * |
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342 * <p> If an exception is thrown from this method then {@link |
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343 * #onError(WebSocket, Throwable) onError} will be invoked with the |
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344 * exception. |
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345 * |
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346 * @implSpec The default implementation {@linkplain WebSocket#request(long) |
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347 * requests one message}. |
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348 * |
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349 * @param webSocket |
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350 * the WebSocket |
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351 */ |
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352 default void onOpen(WebSocket webSocket) { webSocket.request(1); } |
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353 |
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354 /** |
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355 * Receives a Text message. |
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356 * |
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357 * <p> The {@code onText} method is invoked zero or more times between |
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358 * {@code onOpen} and ({@code onClose} or {@code onError}). |
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359 * |
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360 * <p> This message may be a partial UTF-16 sequence. However, the |
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361 * concatenation of all messages through the last will be a whole UTF-16 |
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362 * sequence. |
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363 * |
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364 * <p> If an exception is thrown from this method or the returned {@code |
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365 * CompletionStage} completes exceptionally, then {@link |
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366 * #onError(WebSocket, Throwable) onError} will be invoked with the |
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367 * exception. |
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368 * |
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369 * @implSpec The default implementation {@linkplain WebSocket#request(long) |
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370 * requests one more message}. |
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371 * |
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372 * @implNote This implementation passes only complete UTF-16 sequences |
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373 * to the {@code onText} method. |
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374 * |
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375 * @param webSocket |
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376 * the WebSocket |
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377 * @param message |
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378 * the message |
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379 * @param part |
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380 * the part |
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381 * |
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382 * @return a CompletionStage that completes when the message processing |
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383 * is done; or {@code null} if already done |
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384 */ |
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385 default CompletionStage<?> onText(WebSocket webSocket, |
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386 CharSequence message, |
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387 MessagePart part) { |
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388 webSocket.request(1); |
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389 return null; |
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390 } |
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391 |
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392 /** |
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393 * Receives a Binary message. |
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394 * |
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395 * <p> The {@code onBinary} method is invoked zero or more times |
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396 * between {@code onOpen} and ({@code onClose} or {@code onError}). |
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397 * |
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398 * <p> If an exception is thrown from this method or the returned {@code |
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399 * CompletionStage} completes exceptionally, then {@link |
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400 * #onError(WebSocket, Throwable) onError} will be invoked with this |
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401 * exception. |
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402 * |
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403 * @implSpec The default implementation {@linkplain WebSocket#request(long) |
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404 * requests one more message}. |
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405 * |
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406 * @param webSocket |
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407 * the WebSocket |
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408 * @param message |
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409 * the message |
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410 * @param part |
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411 * the part |
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412 * |
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413 * @return a CompletionStage that completes when the message processing |
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414 * is done; or {@code null} if already done |
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415 */ |
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416 default CompletionStage<?> onBinary(WebSocket webSocket, |
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417 ByteBuffer message, |
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418 MessagePart part) { |
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419 webSocket.request(1); |
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420 return null; |
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421 } |
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422 |
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423 /** |
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424 * Receives a Ping message. |
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425 * |
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426 * <p> A Ping message may be sent or received by either client or |
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427 * server. It may serve either as a keepalive or as a means to verify |
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428 * that the remote endpoint is still responsive. |
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429 * |
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430 * <p> The message will consist of not more than {@code 125} bytes: |
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431 * {@code message.remaining() <= 125}. |
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432 * |
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433 * <p> The {@code onPing} is invoked zero or more times in between |
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434 * {@code onOpen} and ({@code onClose} or {@code onError}). |
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435 * |
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436 * <p> If an exception is thrown from this method or the returned {@code |
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437 * CompletionStage} completes exceptionally, then {@link |
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438 * #onError(WebSocket, Throwable) onError} will be invoked with this |
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439 * exception. |
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440 * |
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441 * @implNote |
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442 * |
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443 * <p> Replies with a Pong message and requests one more message when |
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444 * the Pong has been sent. |
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445 * |
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446 * @param webSocket |
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447 * the WebSocket |
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448 * @param message |
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449 * the message |
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450 * |
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451 * @return a CompletionStage that completes when the message processing |
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452 * is done; or {@code null} if already done |
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453 */ |
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454 default CompletionStage<?> onPing(WebSocket webSocket, |
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455 ByteBuffer message) { |
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456 return webSocket.sendPong(message).thenRun(() -> webSocket.request(1)); |
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457 } |
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458 |
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459 /** |
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460 * Receives a Pong message. |
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461 * |
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462 * <p> A Pong message may be unsolicited or may be received in response |
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463 * to a previously sent Ping. In the latter case, the contents of the |
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464 * Pong is identical to the originating Ping. |
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465 * |
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466 * <p> The message will consist of not more than {@code 125} bytes: |
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467 * {@code message.remaining() <= 125}. |
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468 * |
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469 * <p> The {@code onPong} method is invoked zero or more times in |
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470 * between {@code onOpen} and ({@code onClose} or {@code onError}). |
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471 * |
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472 * <p> If an exception is thrown from this method or the returned {@code |
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473 * CompletionStage} completes exceptionally, then {@link |
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474 * #onError(WebSocket, Throwable) onError} will be invoked with this |
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475 * exception. |
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476 * |
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477 * @implSpec The default implementation {@linkplain WebSocket#request(long) |
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478 * requests one more message}. |
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479 * |
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480 * @param webSocket |
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481 * the WebSocket |
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482 * @param message |
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483 * the message |
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484 * |
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485 * @return a CompletionStage that completes when the message processing |
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486 * is done; or {@code null} if already done |
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487 */ |
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488 default CompletionStage<?> onPong(WebSocket webSocket, |
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489 ByteBuffer message) { |
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490 webSocket.request(1); |
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491 return null; |
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492 } |
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493 |
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494 /** |
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495 * Receives a Close message. |
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496 * |
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497 * <p> Once a Close message is received, the server will not send any |
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498 * more messages. |
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499 * |
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500 * <p> A Close message may consist of a status code and a reason for |
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501 * closing. The reason will have a UTF-8 representation not longer than |
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502 * {@code 123} bytes. The reason may be useful for debugging or passing |
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503 * information relevant to the connection but is not necessarily human |
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504 * readable. |
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505 * |
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506 * <p> {@code onClose} is the last invocation on the {@code Listener}. |
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507 * It is invoked at most once, but after {@code onOpen}. If an exception |
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508 * is thrown from this method, it is ignored. |
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509 * |
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510 * @implSpec The default implementation does nothing. |
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511 * |
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512 * @param webSocket |
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513 * the WebSocket |
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514 * @param code |
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515 * an {@code Optional} describing the close code, or |
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516 * an empty {@code Optional} if the message doesn't contain it |
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517 * @param reason |
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518 * the reason of close; can be empty |
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519 */ |
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520 default void onClose(WebSocket webSocket, Optional<CloseCode> code, |
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521 String reason) { } |
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522 |
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523 /** |
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524 * Notifies an I/O or protocol error has occurred on the {@code |
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525 * WebSocket}. |
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526 * |
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527 * <p> The {@code onError} method does not correspond to any message |
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528 * from the WebSocket Protocol. It is a synthetic event. {@code onError} |
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529 * is the last invocation on the {@code Listener}. It is invoked at most |
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530 * once but after {@code onOpen}. If an exception is thrown from this |
|
531 * method, it is ignored. |
|
532 * |
|
533 * <p> The WebSocket Protocol requires some errors occurs in the |
|
534 * incoming destination must be fatal to the connection. In such cases |
|
535 * the implementation takes care of closing the {@code WebSocket}. By |
|
536 * the time {@code onError} is invoked, no more messages can be sent on |
|
537 * this {@code WebSocket}. |
|
538 * |
|
539 * @apiNote Errors associated with {@code sendX} methods are reported to |
|
540 * the {@code CompletableFuture} these methods return. |
|
541 * |
|
542 * @implSpec The default implementation does nothing. |
|
543 * |
|
544 * @param webSocket |
|
545 * the WebSocket |
|
546 * @param error |
|
547 * the error |
|
548 */ |
|
549 default void onError(WebSocket webSocket, Throwable error) { } |
|
550 } |
|
551 |
|
552 /** |
|
553 * A marker used by {@link WebSocket.Listener} in cases where a partial |
|
554 * message may be received. |
|
555 * |
|
556 * @since 9 |
|
557 */ |
|
558 enum MessagePart { |
|
559 |
|
560 /** |
|
561 * The first part of a message in a sequence. |
|
562 */ |
|
563 FIRST, |
|
564 |
|
565 /** |
|
566 * A middle part of a message in a sequence. |
|
567 */ |
|
568 PART, |
|
569 |
|
570 /** |
|
571 * The last part of a message in a sequence. |
|
572 */ |
|
573 LAST, |
|
574 |
|
575 /** |
|
576 * A whole message consisting of a single part. |
|
577 */ |
|
578 WHOLE |
|
579 } |
|
580 |
|
581 /** |
|
582 * Sends a Text message with characters from the given {@code CharSequence}. |
|
583 * |
|
584 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
585 * normally when the message has been sent or completes exceptionally if an |
|
586 * error occurs. |
|
587 * |
|
588 * <p> The {@code CharSequence} should not be modified until the returned |
|
589 * {@code CompletableFuture} completes (either normally or exceptionally). |
|
590 * |
|
591 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
592 * with: |
|
593 * <ul> |
|
594 * <li> {@link IOException} |
|
595 * if an I/O error occurs during this operation |
|
596 * <li> {@link IllegalStateException} |
|
597 * if the {@code WebSocket} closes while this operation is in progress; |
|
598 * or if a Close message has been sent already; |
|
599 * or if there is an outstanding send operation; |
|
600 * or if a previous Binary message was not sent with {@code isLast == true} |
|
601 * </ul> |
|
602 * |
|
603 * @implNote This implementation does not accept partial UTF-16 |
|
604 * sequences. In case such a sequence is passed, a returned {@code |
|
605 * CompletableFuture} completes exceptionally. |
|
606 * |
|
607 * @param message |
|
608 * the message |
|
609 * @param isLast |
|
610 * {@code true} if this is the last part of the message, |
|
611 * {@code false} otherwise |
|
612 * |
|
613 * @return a CompletableFuture with this WebSocket |
|
614 * |
|
615 * @throws IllegalArgumentException |
|
616 * if {@code message} is a malformed (or an incomplete) UTF-16 sequence |
|
617 */ |
|
618 CompletableFuture<WebSocket> sendText(CharSequence message, boolean isLast); |
|
619 |
|
620 /** |
|
621 * Sends a whole Text message with characters from the given {@code |
|
622 * CharSequence}. |
|
623 * |
|
624 * <p> This is a convenience method. For the general case, use {@link |
|
625 * #sendText(CharSequence, boolean)}. |
|
626 * |
|
627 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
628 * normally when the message has been sent or completes exceptionally if an |
|
629 * error occurs. |
|
630 * |
|
631 * <p> The {@code CharSequence} should not be modified until the returned |
|
632 * {@code CompletableFuture} completes (either normally or exceptionally). |
|
633 * |
|
634 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
635 * with: |
|
636 * <ul> |
|
637 * <li> {@link IOException} |
|
638 * if an I/O error occurs during this operation |
|
639 * <li> {@link IllegalStateException} |
|
640 * if the {@code WebSocket} closes while this operation is in progress; |
|
641 * or if a Close message has been sent already; |
|
642 * or if there is an outstanding send operation; |
|
643 * or if a previous Binary message was not sent with {@code isLast == true} |
|
644 * </ul> |
|
645 * |
|
646 * @param message |
|
647 * the message |
|
648 * |
|
649 * @return a CompletableFuture with this WebSocket |
|
650 * |
|
651 * @throws IllegalArgumentException |
|
652 * if {@code message} is a malformed (or an incomplete) UTF-16 sequence |
|
653 */ |
|
654 default CompletableFuture<WebSocket> sendText(CharSequence message) { |
|
655 return sendText(message, true); |
|
656 } |
|
657 |
|
658 /** |
|
659 * Sends a Binary message with bytes from the given {@code ByteBuffer}. |
|
660 * |
|
661 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
662 * normally when the message has been sent or completes exceptionally if an |
|
663 * error occurs. |
|
664 * |
|
665 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
666 * with: |
|
667 * <ul> |
|
668 * <li> {@link IOException} |
|
669 * if an I/O error occurs during this operation |
|
670 * <li> {@link IllegalStateException} |
|
671 * if the {@code WebSocket} closes while this operation is in progress; |
|
672 * or if a Close message has been sent already; |
|
673 * or if there is an outstanding send operation; |
|
674 * or if a previous Text message was not sent with {@code isLast == true} |
|
675 * </ul> |
|
676 * |
|
677 * @param message |
|
678 * the message |
|
679 * @param isLast |
|
680 * {@code true} if this is the last part of the message, |
|
681 * {@code false} otherwise |
|
682 * |
|
683 * @return a CompletableFuture with this WebSocket |
|
684 */ |
|
685 CompletableFuture<WebSocket> sendBinary(ByteBuffer message, boolean isLast); |
|
686 |
|
687 /** |
|
688 * Sends a Ping message. |
|
689 * |
|
690 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
691 * normally when the message has been sent or completes exceptionally if an |
|
692 * error occurs. |
|
693 * |
|
694 * <p> A Ping message may be sent or received by either client or server. |
|
695 * It may serve either as a keepalive or as a means to verify that the |
|
696 * remote endpoint is still responsive. |
|
697 * |
|
698 * <p> The message must consist of not more than {@code 125} bytes: {@code |
|
699 * message.remaining() <= 125}. |
|
700 * |
|
701 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
702 * with: |
|
703 * <ul> |
|
704 * <li> {@link IOException} |
|
705 * if an I/O error occurs during this operation |
|
706 * <li> {@link IllegalStateException} |
|
707 * if the {@code WebSocket} closes while this operation is in progress; |
|
708 * or if a Close message has been sent already; |
|
709 * or if there is an outstanding send operation |
|
710 * </ul> |
|
711 * |
|
712 * @param message |
|
713 * the message |
|
714 * |
|
715 * @return a CompletableFuture with this WebSocket |
|
716 * |
|
717 * @throws IllegalArgumentException |
|
718 * if {@code message.remaining() > 125} |
|
719 */ |
|
720 CompletableFuture<WebSocket> sendPing(ByteBuffer message); |
|
721 |
|
722 /** |
|
723 * Sends a Pong message. |
|
724 * |
|
725 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
726 * normally when the message has been sent or completes exceptionally if an |
|
727 * error occurs. |
|
728 * |
|
729 * <p> A Pong message may be unsolicited or may be sent in response to a |
|
730 * previously received Ping. In latter case the contents of the Pong is |
|
731 * identical to the originating Ping. |
|
732 * |
|
733 * <p> The message must consist of not more than {@code 125} bytes: {@code |
|
734 * message.remaining() <= 125}. |
|
735 * |
|
736 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
737 * with: |
|
738 * <ul> |
|
739 * <li> {@link IOException} |
|
740 * if an I/O error occurs during this operation |
|
741 * <li> {@link IllegalStateException} |
|
742 * if the {@code WebSocket} closes while this operation is in progress; |
|
743 * or if a Close message has been sent already; |
|
744 * or if there is an outstanding send operation |
|
745 * </ul> |
|
746 * |
|
747 * @param message |
|
748 * the message |
|
749 * |
|
750 * @return a CompletableFuture with this WebSocket |
|
751 * |
|
752 * @throws IllegalArgumentException |
|
753 * if {@code message.remaining() > 125} |
|
754 */ |
|
755 CompletableFuture<WebSocket> sendPong(ByteBuffer message); |
|
756 |
|
757 /** |
|
758 * Sends a Close message with the given close code and the reason. |
|
759 * |
|
760 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
761 * normally when the message has been sent or completes exceptionally if an |
|
762 * error occurs. |
|
763 * |
|
764 * <p> A Close message may consist of a status code and a reason for |
|
765 * closing. The reason must have a UTF-8 representation not longer than |
|
766 * {@code 123} bytes. The reason may be useful for debugging or passing |
|
767 * information relevant to the connection but is not necessarily human |
|
768 * readable. |
|
769 * |
|
770 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
771 * with: |
|
772 * <ul> |
|
773 * <li> {@link IOException} |
|
774 * if an I/O error occurs during this operation |
|
775 * <li> {@link IllegalStateException} |
|
776 * if the {@code WebSocket} closes while this operation is in progress; |
|
777 * or if a Close message has been sent already; |
|
778 * or if there is an outstanding send operation |
|
779 * </ul> |
|
780 * |
|
781 * @param code |
|
782 * the close code |
|
783 * @param reason |
|
784 * the reason; can be empty |
|
785 * |
|
786 * @return a CompletableFuture with this WebSocket |
|
787 * |
|
788 * @throws IllegalArgumentException |
|
789 * if {@code reason} doesn't have an UTF-8 representation not longer |
|
790 * than {@code 123} bytes |
|
791 */ |
|
792 CompletableFuture<WebSocket> sendClose(CloseCode code, CharSequence reason); |
|
793 |
|
794 /** |
|
795 * Sends an empty Close message. |
|
796 * |
|
797 * <p> Returns a {@code CompletableFuture<WebSocket>} which completes |
|
798 * normally when the message has been sent or completes exceptionally if an |
|
799 * error occurs. |
|
800 * |
|
801 * <p> The returned {@code CompletableFuture} can complete exceptionally |
|
802 * with: |
|
803 * <ul> |
|
804 * <li> {@link IOException} |
|
805 * if an I/O error occurs during this operation |
|
806 * <li> {@link IllegalStateException} |
|
807 * if the {@code WebSocket} closes while this operation is in progress; |
|
808 * or if a Close message has been sent already; |
|
809 * or if there is an outstanding send operation |
|
810 * </ul> |
|
811 * |
|
812 * @return a CompletableFuture with this WebSocket |
|
813 */ |
|
814 CompletableFuture<WebSocket> sendClose(); |
|
815 |
|
816 /** |
|
817 * Allows {@code n} more messages to be received by the {@link Listener |
|
818 * Listener}. |
|
819 * |
|
820 * <p> The actual number of received messages might be fewer if a Close |
|
821 * message is received, the connection closes or an error occurs. |
|
822 * |
|
823 * <p> A {@code WebSocket} that has just been created, hasn't requested |
|
824 * anything yet. Usually the initial request for messages is done in {@link |
|
825 * Listener#onOpen(java.net.http.WebSocket) Listener.onOpen}. |
|
826 * |
|
827 * @implNote This implementation does not distinguish between partial and |
|
828 * whole messages, because it's not known beforehand how a message will be |
|
829 * received. |
|
830 * |
|
831 * <p> If a server sends more messages than requested, this implementation |
|
832 * queues up these messages on the TCP connection and may eventually force |
|
833 * the sender to stop sending through TCP flow control. |
|
834 * |
|
835 * @param n |
|
836 * the number of messages |
|
837 * |
|
838 * @throws IllegalArgumentException |
|
839 * if {@code n < 0} |
|
840 */ |
|
841 void request(long n); |
|
842 |
|
843 /** |
|
844 * Returns a {@linkplain Builder#subprotocols(String, String...) subprotocol} |
|
845 * in use. |
|
846 * |
|
847 * @return a subprotocol, or {@code null} if there is none |
|
848 */ |
|
849 String getSubprotocol(); |
|
850 |
|
851 /** |
|
852 * Tells whether the {@code WebSocket} is closed. |
|
853 * |
|
854 * <p> A {@code WebSocket} deemed closed when either the underlying socket |
|
855 * is closed or the closing handshake is completed. |
|
856 * |
|
857 * @return {@code true} if the {@code WebSocket} is closed, |
|
858 * {@code false} otherwise |
|
859 */ |
|
860 boolean isClosed(); |
|
861 |
|
862 /** |
|
863 * Closes the {@code WebSocket} abruptly. |
|
864 * |
|
865 * <p> This method closes the underlying TCP connection. If the {@code |
|
866 * WebSocket} is already closed then invoking this method has no effect. |
|
867 * |
|
868 * @throws IOException |
|
869 * if an I/O error occurs |
|
870 */ |
|
871 void abort() throws IOException; |
|
872 |
|
873 /** |
|
874 * A {@code WebSocket} close status code. |
|
875 * |
|
876 * <p> Some codes <a href="https://tools.ietf.org/html/rfc6455#section-7.4"> |
|
877 * specified</a> in the WebSocket Protocol are defined as named constants |
|
878 * here. Others can be {@linkplain #of(int) retrieved on demand}. |
|
879 * |
|
880 * <p> This is a |
|
881 * <a href="../../lang/doc-files/ValueBased.html">value-based</a> class; |
|
882 * use of identity-sensitive operations (including reference equality |
|
883 * ({@code ==}), identity hash code, or synchronization) on instances of |
|
884 * {@code CloseCode} may have unpredictable results and should be avoided. |
|
885 * |
|
886 * @since 9 |
|
887 */ |
|
888 final class CloseCode { |
|
889 |
|
890 /** |
|
891 * Indicates a normal close, meaning that the purpose for which the |
|
892 * connection was established has been fulfilled. |
|
893 * |
|
894 * <p> Numerical representation: {@code 1000} |
|
895 */ |
|
896 public static final CloseCode NORMAL_CLOSURE |
|
897 = new CloseCode(1000, "NORMAL_CLOSURE"); |
|
898 |
|
899 /** |
|
900 * Indicates that an endpoint is "going away", such as a server going |
|
901 * down or a browser having navigated away from a page. |
|
902 * |
|
903 * <p> Numerical representation: {@code 1001} |
|
904 */ |
|
905 public static final CloseCode GOING_AWAY |
|
906 = new CloseCode(1001, "GOING_AWAY"); |
|
907 |
|
908 /** |
|
909 * Indicates that an endpoint is terminating the connection due to a |
|
910 * protocol error. |
|
911 * |
|
912 * <p> Numerical representation: {@code 1002} |
|
913 */ |
|
914 public static final CloseCode PROTOCOL_ERROR |
|
915 = new CloseCode(1002, "PROTOCOL_ERROR"); |
|
916 |
|
917 /** |
|
918 * Indicates that an endpoint is terminating the connection because it |
|
919 * has received a type of data it cannot accept (e.g., an endpoint that |
|
920 * understands only text data MAY send this if it receives a binary |
|
921 * message). |
|
922 * |
|
923 * <p> Numerical representation: {@code 1003} |
|
924 */ |
|
925 public static final CloseCode CANNOT_ACCEPT |
|
926 = new CloseCode(1003, "CANNOT_ACCEPT"); |
|
927 |
|
928 /** |
|
929 * Indicates that an endpoint is terminating the connection because it |
|
930 * has received data within a message that was not consistent with the |
|
931 * type of the message (e.g., non-UTF-8 [RFC3629] data within a text |
|
932 * message). |
|
933 * |
|
934 * <p> Numerical representation: {@code 1007} |
|
935 */ |
|
936 public static final CloseCode NOT_CONSISTENT |
|
937 = new CloseCode(1007, "NOT_CONSISTENT"); |
|
938 |
|
939 /** |
|
940 * Indicates that an endpoint is terminating the connection because it |
|
941 * has received a message that violates its policy. This is a generic |
|
942 * status code that can be returned when there is no other more suitable |
|
943 * status code (e.g., {@link #CANNOT_ACCEPT} or {@link #TOO_BIG}) or if |
|
944 * there is a need to hide specific details about the policy. |
|
945 * |
|
946 * <p> Numerical representation: {@code 1008} |
|
947 */ |
|
948 public static final CloseCode VIOLATED_POLICY |
|
949 = new CloseCode(1008, "VIOLATED_POLICY"); |
|
950 |
|
951 /** |
|
952 * Indicates that an endpoint is terminating the connection because it |
|
953 * has received a message that is too big for it to process. |
|
954 * |
|
955 * <p> Numerical representation: {@code 1009} |
|
956 */ |
|
957 public static final CloseCode TOO_BIG |
|
958 = new CloseCode(1009, "TOO_BIG"); |
|
959 |
|
960 /** |
|
961 * Indicates that an endpoint is terminating the connection because it |
|
962 * encountered an unexpected condition that prevented it from fulfilling |
|
963 * the request. |
|
964 * |
|
965 * <p> Numerical representation: {@code 1011} |
|
966 */ |
|
967 public static final CloseCode UNEXPECTED_CONDITION |
|
968 = new CloseCode(1011, "UNEXPECTED_CONDITION"); |
|
969 |
|
970 private static final Map<Integer, CloseCode> cached = Map.ofEntries( |
|
971 entry(NORMAL_CLOSURE), |
|
972 entry(GOING_AWAY), |
|
973 entry(PROTOCOL_ERROR), |
|
974 entry(CANNOT_ACCEPT), |
|
975 entry(NOT_CONSISTENT), |
|
976 entry(VIOLATED_POLICY), |
|
977 entry(TOO_BIG), |
|
978 entry(UNEXPECTED_CONDITION) |
|
979 ); |
|
980 |
|
981 /** |
|
982 * Returns a {@code CloseCode} from its numerical representation. |
|
983 * |
|
984 * <p> The given {@code code} should be in the range {@code 1000 <= code |
|
985 * <= 4999}, and should not be equal to any of the following codes: |
|
986 * {@code 1004}, {@code 1005}, {@code 1006} and {@code 1015}. |
|
987 * |
|
988 * @param code |
|
989 * numerical representation |
|
990 * |
|
991 * @return a close code corresponding to the provided numerical value |
|
992 * |
|
993 * @throws IllegalArgumentException |
|
994 * if {@code code} violates any of the requirements above |
|
995 */ |
|
996 public static CloseCode of(int code) { |
|
997 if (code < 1000 || code > 4999) { |
|
998 throw new IllegalArgumentException("Out of range: " + code); |
|
999 } |
|
1000 if (code == 1004 || code == 1005 || code == 1006 || code == 1015) { |
|
1001 throw new IllegalArgumentException("Reserved: " + code); |
|
1002 } |
|
1003 CloseCode closeCode = cached.get(code); |
|
1004 return closeCode != null ? closeCode : new CloseCode(code, ""); |
|
1005 } |
|
1006 |
|
1007 private final int code; |
|
1008 private final String description; |
|
1009 |
|
1010 private CloseCode(int code, String description) { |
|
1011 assert description != null; |
|
1012 this.code = code; |
|
1013 this.description = description; |
|
1014 } |
|
1015 |
|
1016 /** |
|
1017 * Returns a numerical representation of this close code. |
|
1018 * |
|
1019 * @return a numerical representation |
|
1020 */ |
|
1021 public int getCode() { |
|
1022 return code; |
|
1023 } |
|
1024 |
|
1025 /** |
|
1026 * Compares this close code to the specified object. |
|
1027 * |
|
1028 * @param o |
|
1029 * the object to compare this {@code CloseCode} against |
|
1030 * |
|
1031 * @return {@code true} iff the argument is a close code with the same |
|
1032 * {@linkplain #getCode() numerical representation} as this one |
|
1033 */ |
|
1034 @Override |
|
1035 public boolean equals(Object o) { |
|
1036 if (this == o) { |
|
1037 return true; |
|
1038 } |
|
1039 if (!(o instanceof CloseCode)) { |
|
1040 return false; |
|
1041 } |
|
1042 CloseCode that = (CloseCode) o; |
|
1043 return code == that.code; |
|
1044 } |
|
1045 |
|
1046 @Override |
|
1047 public int hashCode() { |
|
1048 return code; |
|
1049 } |
|
1050 |
|
1051 /** |
|
1052 * Returns a human-readable representation of this close code. |
|
1053 * |
|
1054 * @apiNote The representation is not designed to be parsed; the format |
|
1055 * may change unexpectedly. |
|
1056 * |
|
1057 * @return a string representation |
|
1058 */ |
|
1059 @Override |
|
1060 public String toString() { |
|
1061 return code + (description.isEmpty() ? "" : (": " + description)); |
|
1062 } |
|
1063 |
|
1064 private static Map.Entry<Integer, CloseCode> entry(CloseCode cc) { |
|
1065 return Map.entry(cc.getCode(), cc); |
|
1066 } |
|
1067 } |
|
1068 } |
|