Java tutorial
/* * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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 org.elasticsearch.transport.netty4; import io.netty.channel.Channel; import io.netty.channel.ChannelOption; import io.netty.channel.ChannelPromise; import org.elasticsearch.action.ActionListener; import org.elasticsearch.common.bytes.BytesReference; import org.elasticsearch.common.concurrent.CompletableContext; import org.elasticsearch.transport.TcpChannel; import org.elasticsearch.transport.TransportException; import java.net.InetSocketAddress; public class Netty4TcpChannel implements TcpChannel { private final Channel channel; private final String profile; private final CompletableContext<Void> closeContext = new CompletableContext<>(); Netty4TcpChannel(Channel channel, String profile) { this.channel = channel; this.profile = profile; this.channel.closeFuture().addListener(f -> { if (f.isSuccess()) { closeContext.complete(null); } else { Throwable cause = f.cause(); if (cause instanceof Error) { Netty4Utils.maybeDie(cause); closeContext.completeExceptionally(new Exception(cause)); } else { closeContext.completeExceptionally((Exception) cause); } } }); } @Override public void close() { channel.close(); } @Override public String getProfile() { return profile; } @Override public void addCloseListener(ActionListener<Void> listener) { closeContext.addListener(ActionListener.toBiConsumer(listener)); } @Override public void setSoLinger(int value) { channel.config().setOption(ChannelOption.SO_LINGER, value); } @Override public boolean isOpen() { return channel.isOpen(); } @Override public InetSocketAddress getLocalAddress() { return (InetSocketAddress) channel.localAddress(); } @Override public InetSocketAddress getRemoteAddress() { return (InetSocketAddress) channel.remoteAddress(); } @Override public void sendMessage(BytesReference reference, ActionListener<Void> listener) { ChannelPromise writePromise = channel.newPromise(); writePromise.addListener(f -> { if (f.isSuccess()) { listener.onResponse(null); } else { final Throwable cause = f.cause(); Netty4Utils.maybeDie(cause); if (cause instanceof Error) { listener.onFailure(new Exception(cause)); } else { listener.onFailure((Exception) cause); } } }); channel.writeAndFlush(Netty4Utils.toByteBuf(reference), writePromise); if (channel.eventLoop().isShutdown()) { listener.onFailure(new TransportException("Cannot send message, event loop is shutting down.")); } } public Channel getNettyChannel() { return channel; } @Override public String toString() { return "Netty4TcpChannel{" + "localAddress=" + getLocalAddress() + ", remoteAddress=" + channel.remoteAddress() + '}'; } }