Java tutorial
/* * Copyright 2012 The Netty Project * * The Netty Project 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 com.hxr.javatone.concurrency.netty.official.worldclock; import io.netty.channel.Channel; import io.netty.channel.ChannelHandlerContext; import io.netty.channel.SimpleChannelInboundHandler; import com.hxr.javatone.concurrency.netty.official.worldclock.WorldClockProtocol.Continent; import com.hxr.javatone.concurrency.netty.official.worldclock.WorldClockProtocol.LocalTime; import com.hxr.javatone.concurrency.netty.official.worldclock.WorldClockProtocol.LocalTimes; import com.hxr.javatone.concurrency.netty.official.worldclock.WorldClockProtocol.Location; import com.hxr.javatone.concurrency.netty.official.worldclock.WorldClockProtocol.Locations; import java.util.ArrayList; import java.util.Collection; import java.util.Formatter; import java.util.List; import java.util.concurrent.BlockingQueue; import java.util.concurrent.LinkedBlockingQueue; import java.util.logging.Level; import java.util.logging.Logger; import java.util.regex.Pattern; public class WorldClockClientHandler extends SimpleChannelInboundHandler<LocalTimes> { private static final Logger logger = Logger.getLogger(WorldClockClientHandler.class.getName()); private static final Pattern DELIM = Pattern.compile("/"); // Stateful properties private volatile Channel channel; private final BlockingQueue<LocalTimes> answer = new LinkedBlockingQueue<LocalTimes>(); public WorldClockClientHandler() { super(false); } public List<String> getLocalTimes(Collection<String> cities) { Locations.Builder builder = Locations.newBuilder(); for (String c : cities) { String[] components = DELIM.split(c); builder.addLocation(Location.newBuilder().setContinent(Continent.valueOf(components[0].toUpperCase())) .setCity(components[1]).build()); } channel.writeAndFlush(builder.build()); LocalTimes localTimes; boolean interrupted = false; for (;;) { try { localTimes = answer.take(); break; } catch (InterruptedException e) { interrupted = true; } } if (interrupted) { Thread.currentThread().interrupt(); } List<String> result = new ArrayList<String>(); for (LocalTime lt : localTimes.getLocalTimeList()) { result.add(new Formatter().format("%4d-%02d-%02d %02d:%02d:%02d %s", lt.getYear(), lt.getMonth(), lt.getDayOfMonth(), lt.getHour(), lt.getMinute(), lt.getSecond(), lt.getDayOfWeek().name()) .toString()); } return result; } @Override public void channelRegistered(ChannelHandlerContext ctx) throws Exception { channel = ctx.channel(); } @Override public void messageReceived(ChannelHandlerContext ctx, LocalTimes times) throws Exception { answer.add(times); } @Override public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception { logger.log(Level.WARNING, "Unexpected exception from downstream.", cause); ctx.close(); } }