private void startConnection() throws IOException { Launcher<JavaLanguageClient> launcher; ExecutorService executorService = Executors.newCachedThreadPool(); protocol = new JDTLanguageServer(projectsManager, preferenceManager); if (JDTEnvironmentUtils.inSocketStreamDebugMode()) { String host = JDTEnvironmentUtils.getClientHost(); Integer port = JDTEnvironmentUtils.getClientPort(); InetSocketAddress inetSocketAddress = new InetSocketAddress(host, port); AsynchronousServerSocketChannel serverSocket = AsynchronousServerSocketChannel.open().bind(inetSocketAddress); try { AsynchronousSocketChannel socketChannel = serverSocket.accept().get(); InputStream in = Channels.newInputStream(socketChannel); OutputStream out = Channels.newOutputStream(socketChannel); Function<MessageConsumer, MessageConsumer> messageConsumer = it -> it; launcher = Launcher.createIoLauncher(protocol, JavaLanguageClient.class, in, out, executorService, messageConsumer); } catch (InterruptedException | ExecutionException e) { throw new RuntimeException("Error when opening a socket channel at " + host + ":" + port + ".", e); } } else { ConnectionStreamFactory connectionFactory = new ConnectionStreamFactory(); InputStream in = connectionFactory.getInputStream(); OutputStream out = connectionFactory.getOutputStream(); Function<MessageConsumer, MessageConsumer> wrapper = new ParentProcessWatcher(this.languageServer); launcher = Launcher.createLauncher(protocol, JavaLanguageClient.class, in, out, executorService, wrapper); } protocol.connectClient(launcher.getRemoteProxy()); launcher.startListening(); }