com.liferay.sync.engine.lan.server.discovery.LanDiscoveryBroadcaster.java Source code

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Here is the source code for com.liferay.sync.engine.lan.server.discovery.LanDiscoveryBroadcaster.java

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/**
 * Copyright (c) 2000-present Liferay, Inc. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or modify it under
 * the terms of the GNU Lesser General Public License as published by the Free
 * Software Foundation; either version 2.1 of the License, or (at your option)
 * any later version.
 *
 * This library is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more
 * details.
 */

package com.liferay.sync.engine.lan.server.discovery;

import com.liferay.sync.engine.lan.util.LanClientUtil;
import com.liferay.sync.engine.util.JSONUtil;
import com.liferay.sync.engine.util.PropsValues;

import io.netty.bootstrap.Bootstrap;
import io.netty.buffer.Unpooled;
import io.netty.channel.Channel;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.DatagramPacket;
import io.netty.channel.socket.nio.NioDatagramChannel;

import java.net.InetSocketAddress;

/**
 * @author Dennis Ju
 */
public class LanDiscoveryBroadcaster {

    public void broadcast(int port) throws Exception {
        if ((_channel == null) || !_channel.isActive()) {
            _initialize();
        }

        byte[] bytes = JSONUtil.writeValueAsBytes(LanClientUtil.createSyncLanClient(port));

        DatagramPacket datagramPacket = new DatagramPacket(Unpooled.copiedBuffer(bytes),
                new InetSocketAddress("255.255.255.255", PropsValues.SYNC_LAN_SERVER_PORT));

        ChannelFuture channelFuture = _channel.writeAndFlush(datagramPacket);

        channelFuture.sync();
    }

    public void shutdown() {
        if (_eventLoopGroup != null) {
            _eventLoopGroup.shutdownGracefully();
        }
    }

    private void _initialize() throws Exception {
        _eventLoopGroup = new NioEventLoopGroup();

        Bootstrap bootstrap = new Bootstrap();

        bootstrap.channel(NioDatagramChannel.class);
        bootstrap.group(_eventLoopGroup);
        bootstrap.handler(new LanDiscoveryBroadcasterHandler());
        bootstrap.option(ChannelOption.SO_BROADCAST, true);

        ChannelFuture channelFuture = bootstrap.bind(0);

        try {
            channelFuture = channelFuture.sync();

            _channel = channelFuture.channel();
        } catch (InterruptedException ie) {
            _eventLoopGroup.shutdownGracefully();

            throw ie;
        }
    }

    private Channel _channel;
    private EventLoopGroup _eventLoopGroup;

}