Java example source code file (WebSocketServer.java)

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Java - Java tags/keywords

channel, exception, nioeventloopgroup, port, selfsignedcertificate, serverbootstrap, ssl, sslcontext, websocketserver, websocketserverinitializer

The WebSocketServer.java Java example source code

/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.example.http.websocketx.server;

import io.netty.bootstrap.ServerBootstrap;
import io.netty.channel.Channel;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
import io.netty.handler.ssl.SslContext;
import io.netty.handler.ssl.SslContextBuilder;
import io.netty.handler.ssl.util.SelfSignedCertificate;

/**
 * A HTTP server which serves Web Socket requests at:
 *
 * http://localhost:8080/websocket
 *
 * Open your browser at http://localhost:8080/, then the demo page will be loaded and a Web Socket connection will be
 * made automatically.
 *
 * This server illustrates support for the different web socket specification versions and will work with:
 *
 * <ul>
 * <li>Safari 5+ (draft-ietf-hybi-thewebsocketprotocol-00)
 * <li>Chrome 6-13 (draft-ietf-hybi-thewebsocketprotocol-00)
 * <li>Chrome 14+ (draft-ietf-hybi-thewebsocketprotocol-10)
 * <li>Chrome 16+ (RFC 6455 aka draft-ietf-hybi-thewebsocketprotocol-17)
 * <li>Firefox 7+ (draft-ietf-hybi-thewebsocketprotocol-10)
 * <li>Firefox 11+ (RFC 6455 aka draft-ietf-hybi-thewebsocketprotocol-17)
 * </ul>
 */
public final class WebSocketServer {

    static final boolean SSL = System.getProperty("ssl") != null;
    static final int PORT = Integer.parseInt(System.getProperty("port", SSL? "8443" : "8080"));

    public static void main(String[] args) throws Exception {
        // Configure SSL.
        final SslContext sslCtx;
        if (SSL) {
            SelfSignedCertificate ssc = new SelfSignedCertificate();
            sslCtx = SslContextBuilder.forServer(ssc.certificate(), ssc.privateKey()).build();
        } else {
            sslCtx = null;
        }

        EventLoopGroup bossGroup = new NioEventLoopGroup(1);
        EventLoopGroup workerGroup = new NioEventLoopGroup();
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workerGroup)
             .channel(NioServerSocketChannel.class)
             .handler(new LoggingHandler(LogLevel.INFO))
             .childHandler(new WebSocketServerInitializer(sslCtx));

            Channel ch = b.bind(PORT).sync().channel();

            System.out.println("Open your web browser and navigate to " +
                    (SSL? "https" : "http") + "://127.0.0.1:" + PORT + '/');

            ch.closeFuture().sync();
        } finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
}