/*
* 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 io.netty.example.worldclock;
import io.netty.bootstrap.Bootstrap;
import io.netty.channel.Channel;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioSocketChannel;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.regex.Pattern;
/**
* Sends a list of continent/city pairs to a {@link WorldClockServer} to
* get the local times of the specified cities.
*/
public class WorldClockClient {
private final String host;
private final int port;
private final Collection<String> cities;
public WorldClockClient(String host, int port, Collection<String> cities) {
this.host = host;
this.port = port;
this.cities = new ArrayList<String>();
this.cities.addAll(cities);
}
public void run() throws Exception {
Bootstrap b = new Bootstrap();
try {
b.group(new NioEventLoopGroup())
.channel(NioSocketChannel.class)
.handler(new WorldClockClientInitializer());
// Make a new connection.
Channel ch = b.connect(host, port).sync().channel();
// Get the handler instance to initiate the request.
WorldClockClientHandler handler =
ch.pipeline().get(WorldClockClientHandler.class);
// Request and get the response.
List<String> response = handler.getLocalTimes(cities);
// Close the connection.
ch.close();
// Print the response at last but not least.
Iterator<String> i1 = cities.iterator();
Iterator<String> i2 = response.iterator();
while (i1.hasNext()) {
System.out.format("%28s: %s%n", i1.next(), i2.next());
}
} finally {
b.shutdown();
}
}
public static void main(String[] args) throws Exception {
// Print usage if necessary.
if (args.length < 3) {
printUsage();
return;
}
// Parse options.
String host = args[0];
int port = Integer.parseInt(args[1]);
Collection<String> cities = parseCities(args, 2);
if (cities == null) {
return;
}
new WorldClockClient(host, port, cities).run();
}
private static void printUsage() {
System.err.println(
"Usage: " + WorldClockClient.class.getSimpleName() +
" <host> <port> <continent/city_name> ...");
System.err.println(
"Example: " + WorldClockClient.class.getSimpleName() +
" localhost 8080 America/New_York Asia/Seoul");
}
private static final Pattern CITY_PATTERN = Pattern.compile("^[_A-Za-z]+/[_A-Za-z]+$");
private static List<String> parseCities(String[] args, int offset) {
List<String> cities = new ArrayList<String>();
for (int i = offset; i < args.length; i ++) {
if (!CITY_PATTERN.matcher(args[i]).matches()) {
System.err.println("Syntax error: '" + args[i] + '\'');
printUsage();
return null;
}
cities.add(args[i].trim());
}
return cities;
}
}