NetworkService.java

package com.osroyale.game.service;
 
import com.osroyale.Config;
import com.osroyale.OSRoyale;
import com.osroyale.net.ServerPipelineInitializer;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.PooledByteBufAllocator;
import io.netty.channel.ChannelFuture;
import io.netty.channel.ChannelOption;
import io.netty.channel.EventLoopGroup;
import io.netty.channel.WriteBufferWaterMark;
import io.netty.channel.epoll.Epoll;
import io.netty.channel.epoll.EpollEventLoopGroup;
import io.netty.channel.epoll.EpollServerSocketChannel;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.util.ResourceLeakDetector;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
 
import java.util.concurrent.TimeUnit;

 
public final class NetworkService {
 
    private static final Logger logger = LogManager.getLogger(NetworkService.class);
 
    public void start(int port) throws Exception {
        logger.info("Starting network service on port: " + port);
 
        ResourceLeakDetector.setLevel(ResourceLeakDetector.Level.DISABLED);
        final EventLoopGroup bossGroup = Epoll.isAvailable() ? new EpollEventLoopGroup(1) : new NioEventLoopGroup(1);
        final EventLoopGroup workerGroup = Epoll.isAvailable() ? new EpollEventLoopGroup() : new NioEventLoopGroup();
 
        try {
            ServerBootstrap b = new ServerBootstrap();
            b.group(bossGroup, workerGroup)
                    .channel(Epoll.isAvailable() ? EpollServerSocketChannel.class : NioServerSocketChannel.class)
                    .option(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
                    .childOption(ChannelOption.ALLOCATOR, PooledByteBufAllocator.DEFAULT)
                    .childOption(ChannelOption.TCP_NODELAY, true)
                    .childOption(ChannelOption.AUTO_READ, true)
                    .childOption(ChannelOption.WRITE_BUFFER_WATER_MARK, new WriteBufferWaterMark(2 << 16, 2 << 18))
                    .childOption(ChannelOption.SO_SNDBUF, 65536)
                    .childOption(ChannelOption.SO_RCVBUF, 65536)
                    .childOption(ChannelOption.CONNECT_TIMEOUT_MILLIS, 30_000)
                    .childOption(ChannelOption.IP_TOS, Config.IP_TOS)
                    .childHandler(new ServerPipelineInitializer());
 
            ChannelFuture f = b.bind(port).syncUninterruptibly();
 
            OSRoyale.serverStarted.set(true);
 
            logger.info(String.format("Server built successfully (took %d seconds).", OSRoyale.UPTIME.elapsedTime(TimeUnit.SECONDS)));
            OSRoyale.UPTIME.reset();
            f.channel().closeFuture().sync();
        } catch (Exception ex) {
            logger.error("error starting network service.", ex);
        } finally {
            bossGroup.shutdownGracefully();
            workerGroup.shutdownGracefully();
        }
    }
 
}