Example usage for io.netty.handler.ssl SslProvider OPENSSL

List of usage examples for io.netty.handler.ssl SslProvider OPENSSL

Introduction

In this page you can find the example usage for io.netty.handler.ssl SslProvider OPENSSL.

Prototype

SslProvider OPENSSL

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Document

OpenSSL-based implementation.

Usage

From source file:io.netty.example.http2.helloworld.client.Http2Client.java

License:Apache License

public static void main(String[] args) throws Exception {
    // Configure SSL.
    final SslContext sslCtx;
    if (SSL) {/*www  .  j  ava  2  s . com*/
        SslProvider provider = OpenSsl.isAlpnSupported() ? SslProvider.OPENSSL : SslProvider.JDK;
        sslCtx = SslContextBuilder.forClient().sslProvider(provider)
                /* NOTE: the cipher filter may not include all ciphers required by the HTTP/2 specification.
                 * Please refer to the HTTP/2 specification for cipher requirements. */
                .ciphers(Http2SecurityUtil.CIPHERS, SupportedCipherSuiteFilter.INSTANCE)
                .trustManager(InsecureTrustManagerFactory.INSTANCE)
                .applicationProtocolConfig(new ApplicationProtocolConfig(Protocol.ALPN,
                        // NO_ADVERTISE is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectorFailureBehavior.NO_ADVERTISE,
                        // ACCEPT is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectedListenerFailureBehavior.ACCEPT, ApplicationProtocolNames.HTTP_2,
                        ApplicationProtocolNames.HTTP_1_1))
                .build();
    } else {
        sslCtx = null;
    }

    EventLoopGroup workerGroup = new NioEventLoopGroup();
    Http2ClientInitializer initializer = new Http2ClientInitializer(sslCtx, Integer.MAX_VALUE);

    try {
        // Configure the client.
        Bootstrap b = new Bootstrap();
        b.group(workerGroup);
        b.channel(NioSocketChannel.class);
        b.option(ChannelOption.SO_KEEPALIVE, true);
        b.remoteAddress(HOST, PORT);
        b.handler(initializer);

        // Start the client.
        Channel channel = b.connect().syncUninterruptibly().channel();
        System.out.println("Connected to [" + HOST + ':' + PORT + ']');

        // Wait for the HTTP/2 upgrade to occur.
        Http2SettingsHandler http2SettingsHandler = initializer.settingsHandler();
        http2SettingsHandler.awaitSettings(5, TimeUnit.SECONDS);

        HttpResponseHandler responseHandler = initializer.responseHandler();
        int streamId = 3;
        HttpScheme scheme = SSL ? HttpScheme.HTTPS : HttpScheme.HTTP;
        AsciiString hostName = new AsciiString(HOST + ':' + PORT);
        System.err.println("Sending request(s)...");
        if (URL != null) {
            // Create a simple GET request.
            FullHttpRequest request = new DefaultFullHttpRequest(HTTP_1_1, GET, URL, Unpooled.EMPTY_BUFFER);
            request.headers().add(HttpHeaderNames.HOST, hostName);
            request.headers().add(HttpConversionUtil.ExtensionHeaderNames.SCHEME.text(), scheme.name());
            request.headers().add(HttpHeaderNames.ACCEPT_ENCODING, HttpHeaderValues.GZIP);
            request.headers().add(HttpHeaderNames.ACCEPT_ENCODING, HttpHeaderValues.DEFLATE);
            responseHandler.put(streamId, channel.write(request), channel.newPromise());
            streamId += 2;
        }
        if (URL2 != null) {
            // Create a simple POST request with a body.
            FullHttpRequest request = new DefaultFullHttpRequest(HTTP_1_1, POST, URL2,
                    wrappedBuffer(URL2DATA.getBytes(CharsetUtil.UTF_8)));
            request.headers().add(HttpHeaderNames.HOST, hostName);
            request.headers().add(HttpConversionUtil.ExtensionHeaderNames.SCHEME.text(), scheme.name());
            request.headers().add(HttpHeaderNames.ACCEPT_ENCODING, HttpHeaderValues.GZIP);
            request.headers().add(HttpHeaderNames.ACCEPT_ENCODING, HttpHeaderValues.DEFLATE);
            responseHandler.put(streamId, channel.write(request), channel.newPromise());
        }
        channel.flush();
        responseHandler.awaitResponses(5, TimeUnit.SECONDS);
        System.out.println("Finished HTTP/2 request(s)");

        // Wait until the connection is closed.
        channel.close().syncUninterruptibly();
    } finally {
        workerGroup.shutdownGracefully();
    }
}

From source file:io.netty.example.ocsp.OcspClientExample.java

License:Apache License

public static void main(String[] args) throws Exception {
    if (!OpenSsl.isAvailable()) {
        throw new IllegalStateException("OpenSSL is not available!");
    }//from   ww w  . j  a v a2 s.  c  o m

    if (!OpenSsl.isOcspSupported()) {
        throw new IllegalStateException("OCSP is not supported!");
    }

    // Using Wikipedia as an example. I'd rather use Netty's own website
    // but the server (Cloudflare) doesn't support OCSP stapling. A few
    // other examples could be Microsoft or Squarespace. Use OpenSSL's
    // CLI client to assess if a server supports OCSP stapling. E.g.:
    //
    // openssl s_client -tlsextdebug -status -connect www.squarespace.com:443
    //
    String host = "www.wikipedia.org";

    ReferenceCountedOpenSslContext context = (ReferenceCountedOpenSslContext) SslContextBuilder.forClient()
            .sslProvider(SslProvider.OPENSSL).enableOcsp(true).build();

    try {
        EventLoopGroup group = new NioEventLoopGroup();
        try {
            Promise<FullHttpResponse> promise = group.next().newPromise();

            Bootstrap bootstrap = new Bootstrap().channel(NioSocketChannel.class).group(group)
                    .option(ChannelOption.CONNECT_TIMEOUT_MILLIS, 5 * 1000)
                    .handler(newClientHandler(context, host, promise));

            Channel channel = bootstrap.connect(host, 443).syncUninterruptibly().channel();

            try {
                FullHttpResponse response = promise.get();
                ReferenceCountUtil.release(response);
            } finally {
                channel.close();
            }
        } finally {
            group.shutdownGracefully();
        }
    } finally {
        context.release();
    }
}

From source file:io.netty.example.ocsp.OcspServerExample.java

License:Apache License

public static void main(String[] args) throws Exception {
    // We assume there's a private key.
    PrivateKey privateKey = null;

    // Step 1: Load the certificate chain for netty.io. We'll need the certificate
    // and the issuer's certificate and we don't need any of the intermediate certs.
    // The array is assumed to be a certain order to keep things simple.
    X509Certificate[] keyCertChain = parseCertificates(OcspServerExample.class, "netty_io_chain.pem");

    X509Certificate certificate = keyCertChain[0];
    X509Certificate issuer = keyCertChain[keyCertChain.length - 1];

    // Step 2: We need the URL of the CA's OCSP responder server. It's somewhere encoded
    // into the certificate! Notice that it's an HTTP URL.
    URI uri = OcspUtils.ocspUri(certificate);
    System.out.println("OCSP Responder URI: " + uri);

    if (uri == null) {
        throw new IllegalStateException("The CA/certificate doesn't have an OCSP responder");
    }/* www  .j a v a2  s.com*/

    // Step 3: Construct the OCSP request
    OCSPReq request = new OcspRequestBuilder().certificate(certificate).issuer(issuer).build();

    // Step 4: Do the request to the CA's OCSP responder
    OCSPResp response = OcspUtils.request(uri, request, 5L, TimeUnit.SECONDS);
    if (response.getStatus() != OCSPResponseStatus.SUCCESSFUL) {
        throw new IllegalStateException("response-status=" + response.getStatus());
    }

    // Step 5: Is my certificate any good or has the CA revoked it?
    BasicOCSPResp basicResponse = (BasicOCSPResp) response.getResponseObject();
    SingleResp first = basicResponse.getResponses()[0];

    CertificateStatus status = first.getCertStatus();
    System.out.println("Status: " + (status == CertificateStatus.GOOD ? "Good" : status));
    System.out.println("This Update: " + first.getThisUpdate());
    System.out.println("Next Update: " + first.getNextUpdate());

    if (status != null) {
        throw new IllegalStateException("certificate-status=" + status);
    }

    BigInteger certSerial = certificate.getSerialNumber();
    BigInteger ocspSerial = first.getCertID().getSerialNumber();
    if (!certSerial.equals(ocspSerial)) {
        throw new IllegalStateException("Bad Serials=" + certSerial + " vs. " + ocspSerial);
    }

    // Step 6: Cache the OCSP response and use it as long as it's not
    // expired. The exact semantics are beyond the scope of this example.

    if (!OpenSsl.isAvailable()) {
        throw new IllegalStateException("OpenSSL is not available!");
    }

    if (!OpenSsl.isOcspSupported()) {
        throw new IllegalStateException("OCSP is not supported!");
    }

    if (privateKey == null) {
        throw new IllegalStateException(
                "Because we don't have a PrivateKey we can't continue past this point.");
    }

    ReferenceCountedOpenSslContext context = (ReferenceCountedOpenSslContext) SslContextBuilder
            .forServer(privateKey, keyCertChain).sslProvider(SslProvider.OPENSSL).enableOcsp(true).build();

    try {
        ServerBootstrap bootstrap = new ServerBootstrap().childHandler(newServerHandler(context, response));

        // so on and so forth...
    } finally {
        context.release();
    }
}

From source file:io.spikex.core.util.connection.KeyStoreHelper.java

License:Apache License

public SslContext buildOpenSslClientContext(final boolean clientAuth) throws IOException {

    SslContext ctx;/* www.j  a  v  a 2s. co  m*/

    if (clientAuth) {
        ctx = SslContextBuilder.forClient().sslProvider(SslProvider.OPENSSL)
                .trustManager(getTrustCertChainPath().toAbsolutePath().normalize().toFile())
                .keyManager(getClientCertPath().toAbsolutePath().normalize().toFile(),
                        getClientKeyPath().toAbsolutePath().normalize().toFile())
                .build();
    } else {
        ctx = SslContextBuilder.forClient().sslProvider(SslProvider.OPENSSL)
                .trustManager(getTrustCertChainPath().toAbsolutePath().normalize().toFile()).build();
    }

    return ctx;
}

From source file:io.vertx.core.net.impl.SSLHelper.java

License:Open Source License

private SslContext createContext(VertxInternal vertx) {
    try {/*from www  .  j ava  2s.c  o m*/
        KeyManagerFactory keyMgrFactory = getKeyMgrFactory(vertx);
        TrustManagerFactory trustMgrFactory = getTrustMgrFactory(vertx);
        SslContextBuilder builder;
        if (client) {
            builder = SslContextBuilder.forClient();
            if (keyMgrFactory != null) {
                builder.keyManager(keyMgrFactory);
            }
        } else {
            if (keyMgrFactory == null) {
                throw new VertxException("Key/certificate is mandatory for SSL");
            }
            builder = SslContextBuilder.forServer(keyMgrFactory);
        }
        Collection<String> cipherSuites = enabledCipherSuites;
        if (openSsl) {
            builder.sslProvider(SslProvider.OPENSSL);
            if (cipherSuites == null || cipherSuites.isEmpty()) {
                cipherSuites = OpenSsl.availableOpenSslCipherSuites();
            }
        } else {
            builder.sslProvider(SslProvider.JDK);
            if (cipherSuites == null || cipherSuites.isEmpty()) {
                cipherSuites = DEFAULT_JDK_CIPHER_SUITE;
            }
        }
        if (trustMgrFactory != null) {
            builder.trustManager(trustMgrFactory);
        }
        if (cipherSuites != null && cipherSuites.size() > 0) {
            builder.ciphers(cipherSuites);
        }
        if (useAlpn && applicationProtocols != null && applicationProtocols.size() > 0) {
            builder.applicationProtocolConfig(new ApplicationProtocolConfig(
                    ApplicationProtocolConfig.Protocol.ALPN,
                    ApplicationProtocolConfig.SelectorFailureBehavior.NO_ADVERTISE,
                    ApplicationProtocolConfig.SelectedListenerFailureBehavior.ACCEPT, applicationProtocols
                            .stream().map(PROTOCOL_NAME_MAPPING::get).collect(Collectors.toList())));
        }
        return builder.build();
    } catch (Exception e) {
        throw new VertxException(e);
    }
}

From source file:jmeter.plugins.http2.sampler.NettyHttp2Client.java

License:Apache License

private SslContext getSslContext() {
    SslContext sslCtx = null;//from www .j a  va  2s.com

    final SslProvider provider = OpenSsl.isAlpnSupported() ? SslProvider.OPENSSL : SslProvider.JDK;

    try {
        sslCtx = SslContextBuilder.forClient().sslProvider(provider)
                .ciphers(Http2SecurityUtil.CIPHERS, SupportedCipherSuiteFilter.INSTANCE)
                .trustManager(InsecureTrustManagerFactory.INSTANCE)
                .applicationProtocolConfig(
                        new ApplicationProtocolConfig(Protocol.ALPN, SelectorFailureBehavior.NO_ADVERTISE,
                                SelectedListenerFailureBehavior.ACCEPT, ApplicationProtocolNames.HTTP_2))
                .build();
    } catch (SSLException exception) {
        return null;
    }

    return sslCtx;
}

From source file:majordodo.network.netty.NettyChannelAcceptor.java

License:Apache License

public void start() throws Exception {
    boolean useOpenSSL = NetworkUtils.isOpenSslAvailable();
    if (ssl) {//from w ww  .  jav  a2s  . c  om

        if (sslCertFile == null) {
            LOGGER.log(Level.SEVERE,
                    "start SSL with self-signed auto-generated certificate, useOpenSSL:" + useOpenSSL);
            if (sslCiphers != null) {
                LOGGER.log(Level.SEVERE, "required sslCiphers " + sslCiphers);
            }
            SelfSignedCertificate ssc = new SelfSignedCertificate();
            try {
                sslCtx = SslContextBuilder.forServer(ssc.certificate(), ssc.privateKey())
                        .sslProvider(useOpenSSL ? SslProvider.OPENSSL : SslProvider.JDK).ciphers(sslCiphers)
                        .build();
            } finally {
                ssc.delete();
            }
        } else {
            LOGGER.log(Level.SEVERE, "start SSL with certificate " + sslCertFile.getAbsolutePath()
                    + " chain file " + sslCertChainFile.getAbsolutePath() + " , useOpenSSL:" + useOpenSSL);
            if (sslCiphers != null) {
                LOGGER.log(Level.SEVERE, "required sslCiphers " + sslCiphers);
            }
            sslCtx = SslContextBuilder.forServer(sslCertChainFile, sslCertFile, sslCertPassword)
                    .sslProvider(useOpenSSL ? SslProvider.OPENSSL : SslProvider.JDK).ciphers(sslCiphers)
                    .build();
        }

    }
    if (NetworkUtils.isEnableEpollNative()) {
        bossGroup = new EpollEventLoopGroup(workerThreads);
        workerGroup = new EpollEventLoopGroup(workerThreads);
        LOGGER.log(Level.INFO, "Using netty-native-epoll network type");
    } else {
        bossGroup = new NioEventLoopGroup(workerThreads);
        workerGroup = new NioEventLoopGroup(workerThreads);
    }
    ServerBootstrap b = new ServerBootstrap();
    b.group(bossGroup, workerGroup).channel(
            NetworkUtils.isEnableEpollNative() ? EpollServerSocketChannel.class : NioServerSocketChannel.class)
            .childHandler(new ChannelInitializer<SocketChannel>() {
                @Override
                public void initChannel(SocketChannel ch) throws Exception {
                    NettyChannel session = new NettyChannel("client", ch, callbackExecutor, null);
                    if (acceptor != null) {
                        acceptor.createConnection(session);
                    }

                    //                        ch.pipeline().addLast(new LoggingHandler());
                    // Add SSL handler first to encrypt and decrypt everything.
                    if (ssl) {
                        ch.pipeline().addLast(sslCtx.newHandler(ch.alloc()));
                    }

                    ch.pipeline().addLast("lengthprepender", new LengthFieldPrepender(4));
                    ch.pipeline().addLast("lengthbaseddecoder",
                            new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4));
                    //
                    ch.pipeline().addLast("messageencoder", new DodoMessageEncoder());
                    ch.pipeline().addLast("messagedecoder", new DodoMessageDecoder());
                    ch.pipeline().addLast(new InboundMessageHandler(session));
                }
            }).option(ChannelOption.SO_BACKLOG, 128).childOption(ChannelOption.SO_KEEPALIVE, true);

    ChannelFuture f = b.bind(host, port).sync(); // (7)
    this.channel = f.channel();

}

From source file:majordodo.network.netty.NettyConnector.java

License:Apache License

public NettyChannel connect() throws Exception {
    boolean useOpenSSL = NetworkUtils.isOpenSslAvailable();
    if (ssl) {/*from   w w  w  . j  av a 2  s. c om*/
        if (sslUnsecure) {
            this.sslCtx = SslContextBuilder.forClient()
                    .sslProvider(useOpenSSL ? SslProvider.OPENSSL : SslProvider.JDK)
                    .trustManager(InsecureTrustManagerFactory.INSTANCE).build();
        } else {
            this.sslCtx = SslContextBuilder.forClient()
                    .sslProvider(useOpenSSL ? SslProvider.OPENSSL : SslProvider.JDK).build();
        }
    }
    if (NetworkUtils.isEnableEpollNative()) {
        group = new EpollEventLoopGroup();
    } else {
        group = new NioEventLoopGroup();
    }
    LOG.log(Level.INFO, "Trying to connect to broker at " + host + ":" + port + " ssl:" + ssl + ", sslUnsecure:"
            + sslUnsecure + " openSsl:" + useOpenSSL);

    Bootstrap b = new Bootstrap();
    b.group(group)
            .channel(NetworkUtils.isEnableEpollNative() ? EpollSocketChannel.class : NioSocketChannel.class)
            .option(ChannelOption.TCP_NODELAY, true).handler(new ChannelInitializer<SocketChannel>() {
                @Override
                public void initChannel(SocketChannel ch) throws Exception {
                    channel = new NettyChannel(host + ":" + port, ch, callbackExecutor, NettyConnector.this);
                    channel.setMessagesReceiver(receiver);
                    channel.setRemoteHost(host);
                    if (ssl) {
                        ch.pipeline().addLast(sslCtx.newHandler(ch.alloc(), host, port));
                    }
                    ch.pipeline().addLast("lengthprepender", new LengthFieldPrepender(4));
                    ch.pipeline().addLast("lengthbaseddecoder",
                            new LengthFieldBasedFrameDecoder(Integer.MAX_VALUE, 0, 4, 0, 4));
                    //
                    ch.pipeline().addLast("messageencoder", new DodoMessageEncoder());
                    ch.pipeline().addLast("messagedecoder", new DodoMessageDecoder());
                    ch.pipeline().addLast(new InboundMessageHandler(channel));
                }
            });

    ChannelFuture f = b.connect(host, port).sync();
    socketchannel = f.channel();
    return channel;

}

From source file:me.netty.http.HttpServer.java

License:Apache License

public void start() throws Exception {
    //?// ww w  . j a v  a2 s  .c  o m
    serverContext.initContext();

    // Configure SSL.
    final SslContext sslCtx;
    if (SSL) {
        SslProvider provider = OpenSsl.isAlpnSupported() ? SslProvider.OPENSSL : SslProvider.JDK;
        SelfSignedCertificate ssc = new SelfSignedCertificate();
        sslCtx = SslContextBuilder.forServer(ssc.certificate(), ssc.privateKey()).sslProvider(provider)
                /* NOTE: the cipher filter may not include all ciphers required by the HTTP/2 specification.
                 * Please refer to the HTTP/2 specification for cipher requirements. */
                .ciphers(Http2SecurityUtil.CIPHERS, SupportedCipherSuiteFilter.INSTANCE)
                .applicationProtocolConfig(new ApplicationProtocolConfig(Protocol.ALPN,
                        // NO_ADVERTISE is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectorFailureBehavior.NO_ADVERTISE,
                        // ACCEPT is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectedListenerFailureBehavior.ACCEPT, ApplicationProtocolNames.HTTP_2,
                        ApplicationProtocolNames.HTTP_1_1))
                .build();
    } else {
        sslCtx = null;
    }
    // Configure the http2Orhttp.

    //CPU??workwork?
    // ?????
    int threads = Runtime.getRuntime().availableProcessors() * 2;

    EventLoopGroup bossGroup = new NioEventLoopGroup(threads);
    EventLoopGroup workerGroup = new NioEventLoopGroup(threads);
    try {
        ServerBootstrap b = new ServerBootstrap();
        b.option(ChannelOption.SO_BACKLOG, 1024);
        b.group(bossGroup, workerGroup).channel(NioServerSocketChannel.class)
                .handler(new LoggingHandler(LogLevel.DEBUG)).childHandler(new Http2ServerInitializer(sslCtx));

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

        logger.info("Open your HTTP/2-enabled web browser and navigate to " + (SSL ? "https" : "http")
                + "://127.0.0.1:" + PORT + '/');

        ch.closeFuture().sync().addListener(new GenericFutureListener<Future<? super Void>>() {
            public void operationComplete(Future<? super Void> future) throws Exception {
                logger.info("service has shutdown");
            }
        });
    } finally {
        bossGroup.shutdownGracefully();
        workerGroup.shutdownGracefully();
    }

}

From source file:netty.http2.ConcurrentHttp2Client.java

License:Apache License

public static void main(String[] args) throws Exception {
    // Configure SSL.
    final SslContext sslCtx;
    if (SSL) {//from   w w  w  .ja  v  a  2  s .  co  m
        SslProvider provider = OpenSsl.isAlpnSupported() ? SslProvider.OPENSSL : SslProvider.JDK;
        sslCtx = SslContextBuilder.forClient().sslProvider(provider)
                /* NOTE: the cipher filter may not include all ciphers required by the HTTP/2 specification.
                 * Please refer to the HTTP/2 specification for cipher requirements. */
                .ciphers(Http2SecurityUtil.CIPHERS, SupportedCipherSuiteFilter.INSTANCE)
                .trustManager(InsecureTrustManagerFactory.INSTANCE)
                .applicationProtocolConfig(new ApplicationProtocolConfig(Protocol.ALPN,
                        // NO_ADVERTISE is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectorFailureBehavior.NO_ADVERTISE,
                        // ACCEPT is currently the only mode supported by both OpenSsl and JDK providers.
                        SelectedListenerFailureBehavior.ACCEPT, ApplicationProtocolNames.HTTP_2,
                        ApplicationProtocolNames.HTTP_1_1))
                .build();
    } else {
        sslCtx = null;
    }

    EventLoopGroup workerGroup = new NioEventLoopGroup();
    ConcurrentHttp2ClientInitializer initializer = new ConcurrentHttp2ClientInitializer();

    try {
        // Configure the client.
        Bootstrap bootstrap = new Bootstrap();
        bootstrap.group(workerGroup);
        bootstrap.channel(NioSocketChannel.class);
        bootstrap.option(ChannelOption.SO_KEEPALIVE, true);
        bootstrap.remoteAddress(HOST, PORT);
        bootstrap.handler(initializer);

        // Start the client.
        Channel channel = bootstrap.connect().syncUninterruptibly().channel();
        System.out.println("Connected to [" + HOST + ':' + PORT + ']');

        HttpScheme scheme = SSL ? HttpScheme.HTTPS : HttpScheme.HTTP;
        AsciiString hostName = new AsciiString(HOST + ':' + PORT);
        System.err.println("Sending request(s)...");
        if (URL != null) {
            // Create a simple GET request.
            for (int i = 0; i < 1; i++) {
                StreamRequest request = new StreamRequestBuilder(new URI(URL)).setMethod("GET")
                        //.setMethod("POST")
                        .setHeader(HttpHeaderNames.HOST.toString(), hostName.toString())
                        //.build(EntityStreams.emptyStream());
                        .build(EntityStreams
                                .newEntityStream(new ByteStringWriter(ByteString.copy(new byte[0 * 1024]))));
                channel.writeAndFlush(request);
                System.err.println("Sent request #" + i);
            }
        }
        System.err.println("Finished HTTP/2 request(s)");
        long start = System.currentTimeMillis();

        // Wait until the connection is closed.
        channel.closeFuture().sync();

        long end = System.currentTimeMillis();
        System.err.println("Server Idled for: " + (end - start) + " milliseconds");
    } finally {
        workerGroup.shutdownGracefully();
    }
}