Java tutorial
/** * Copyright (C) 2010-2013 Alibaba Group Holding Limited * * Licensed 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 com.alibaba.rocketmq.remoting.common; import io.netty.channel.Channel; import io.netty.channel.ChannelFuture; import io.netty.channel.ChannelFutureListener; import java.io.IOException; import java.lang.reflect.Method; import java.net.Inet6Address; import java.net.InetAddress; import java.net.InetSocketAddress; import java.net.NetworkInterface; import java.net.SocketAddress; import java.net.SocketException; import java.net.UnknownHostException; import java.nio.channels.Selector; import java.nio.channels.SocketChannel; import java.nio.channels.spi.SelectorProvider; import java.util.ArrayList; import java.util.Enumeration; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * * * @author shijia.wxr<vintage.wang@gmail.com> * @since 2013-7-13 */ public class RemotingUtil { private static final Logger log = LoggerFactory.getLogger(RemotingHelper.RemotingLogName); public static final String OS_NAME = System.getProperty("os.name"); private static boolean isLinuxPlatform = false; private static boolean isWindowsPlatform = false; static { if (OS_NAME != null && OS_NAME.toLowerCase().indexOf("linux") >= 0) { isLinuxPlatform = true; } if (OS_NAME != null && OS_NAME.toLowerCase().indexOf("windows") >= 0) { isWindowsPlatform = true; } } public static boolean isLinuxPlatform() { return isLinuxPlatform; } public static boolean isWindowsPlatform() { return isWindowsPlatform; } public static Selector openSelector() throws IOException { Selector result = null; // linux???epoll if (isLinuxPlatform()) { try { final Class<?> providerClazz = Class.forName("sun.nio.ch.EPollSelectorProvider"); if (providerClazz != null) { try { final Method method = providerClazz.getMethod("provider"); if (method != null) { final SelectorProvider selectorProvider = (SelectorProvider) method.invoke(null); if (selectorProvider != null) { result = selectorProvider.openSelector(); } } } catch (final Exception e) { // ignore } } } catch (final Exception e) { // ignore } } if (result == null) { result = Selector.open(); } return result; } public static String getLocalAddress() { try { // Traversal Network interface to get the first non-loopback and non-private address Enumeration<NetworkInterface> enumeration = NetworkInterface.getNetworkInterfaces(); ArrayList<String> ipv4Result = new ArrayList<String>(); ArrayList<String> ipv6Result = new ArrayList<String>(); while (enumeration.hasMoreElements()) { final NetworkInterface networkInterface = enumeration.nextElement(); final Enumeration<InetAddress> en = networkInterface.getInetAddresses(); while (en.hasMoreElements()) { final InetAddress address = en.nextElement(); if (!address.isLoopbackAddress()) { if (address instanceof Inet6Address) { ipv6Result.add(normalizeHostAddress(address)); } else { ipv4Result.add(normalizeHostAddress(address)); } } } } // prefer ipv4 if (!ipv4Result.isEmpty()) { for (String ip : ipv4Result) { if (ip.startsWith("127.0") || ip.startsWith("192.168")) { continue; } return ip; } return ipv4Result.get(ipv4Result.size() - 1); } else if (!ipv6Result.isEmpty()) { return ipv6Result.get(0); } //If failed to find,fall back to localhost final InetAddress localHost = InetAddress.getLocalHost(); return normalizeHostAddress(localHost); } catch (SocketException e) { e.printStackTrace(); } catch (UnknownHostException e) { e.printStackTrace(); } return null; } public static String normalizeHostAddress(final InetAddress localHost) { if (localHost instanceof Inet6Address) { return "[" + localHost.getHostAddress() + "]"; } else { return localHost.getHostAddress(); } } /** * IP:PORT */ public static SocketAddress string2SocketAddress(final String addr) { String[] s = addr.split(":"); InetSocketAddress isa = new InetSocketAddress(s[0], Integer.valueOf(s[1])); return isa; } public static String socketAddress2String(final SocketAddress addr) { StringBuilder sb = new StringBuilder(); InetSocketAddress inetSocketAddress = (InetSocketAddress) addr; sb.append(inetSocketAddress.getAddress().getHostAddress()); sb.append(":"); sb.append(inetSocketAddress.getPort()); return sb.toString(); } public static SocketChannel connect(SocketAddress remote) { return connect(remote, 1000 * 5); } public static SocketChannel connect(SocketAddress remote, final int timeoutMillis) { SocketChannel sc = null; try { sc = SocketChannel.open(); sc.configureBlocking(true); sc.socket().setSoLinger(false, -1); sc.socket().setTcpNoDelay(true); sc.socket().setReceiveBufferSize(1024 * 64); sc.socket().setSendBufferSize(1024 * 64); sc.socket().connect(remote, timeoutMillis); sc.configureBlocking(false); return sc; } catch (Exception e) { if (sc != null) { try { sc.close(); } catch (IOException e1) { e1.printStackTrace(); } } } return null; } public static void closeChannel(Channel channel) { final String addrRemote = RemotingHelper.parseChannelRemoteAddr(channel); channel.close().addListener(new ChannelFutureListener() { @Override public void operationComplete(ChannelFuture future) throws Exception { log.info("closeChannel: close the connection to remote address[{}] result: {}", addrRemote, future.isSuccess()); } }); } }