Java tutorial
/* * Copyright (c) 2011-2013 The original author or authors * ------------------------------------------------------ * All rights reserved. This program and the accompanying materials * are made available under the terms of the Eclipse Public License v1.0 * and Apache License v2.0 which accompanies this distribution. * * The Eclipse Public License is available at * http://www.eclipse.org/legal/epl-v10.html * * The Apache License v2.0 is available at * http://www.opensource.org/licenses/apache2.0.php * * You may elect to redistribute this code under either of these licenses. */ package io.vertx.core.net.impl; import io.netty.bootstrap.Bootstrap; import io.netty.bootstrap.ServerBootstrap; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.vertx.core.AsyncResult; import io.vertx.core.Future; import io.vertx.core.Handler; import io.vertx.core.impl.VertxInternal; import java.net.InetSocketAddress; import java.util.ArrayList; import java.util.List; import java.util.function.Function; /** * @author <a href="http://tfox.org">Tim Fox</a> */ public class AsyncResolveBindConnectHelper { private List<Handler<AsyncResult<Channel>>> handlers = new ArrayList<>(); private ChannelFuture future; private AsyncResult<Channel> result; public synchronized void addListener(Handler<AsyncResult<Channel>> handler) { if (result != null) { if (future != null) { future.addListener(v -> handler.handle(result)); } else { handler.handle(result); } } else { handlers.add(handler); } } private synchronized void handle(ChannelFuture cf, AsyncResult<Channel> res) { if (result == null) { for (Handler<AsyncResult<Channel>> handler : handlers) { handler.handle(res); } future = cf; result = res; } else { throw new IllegalStateException("Already complete!"); } } private static void checkPort(int port) { if (port < 0 || port > 65535) { throw new IllegalArgumentException("Invalid port " + port); } } public static AsyncResolveBindConnectHelper doBind(VertxInternal vertx, int port, String host, ServerBootstrap bootstrap) { return doBindConnect(vertx, port, host, bootstrap::bind); } public static AsyncResolveBindConnectHelper doConnect(VertxInternal vertx, int port, String host, Bootstrap bootstrap) { return doBindConnect(vertx, port, host, bootstrap::connect); } private static AsyncResolveBindConnectHelper doBindConnect(VertxInternal vertx, int port, String host, Function<InetSocketAddress, ChannelFuture> cfProducer) { checkPort(port); AsyncResolveBindConnectHelper asyncResolveBindConnectHelper = new AsyncResolveBindConnectHelper(); vertx.resolveHostname(host, res -> { if (res.succeeded()) { // At this point the name is an IP address so there will be no resolve hit InetSocketAddress t = new InetSocketAddress(res.result(), port); ChannelFuture future = cfProducer.apply(t); future.addListener(f -> { if (f.isSuccess()) { asyncResolveBindConnectHelper.handle(future, Future.succeededFuture(future.channel())); } else { asyncResolveBindConnectHelper.handle(future, Future.failedFuture(f.cause())); } }); } else { asyncResolveBindConnectHelper.handle(null, Future.failedFuture(res.cause())); } }); return asyncResolveBindConnectHelper; } }