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@terefang
Created November 16, 2021 00:19
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package netty4.example;
import io.netty.bootstrap.ServerBootstrap;
import io.netty.buffer.AbstractByteBuf;
import io.netty.buffer.ByteBuf;
import io.netty.buffer.ByteBufUtil;
import io.netty.channel.*;
import io.netty.channel.nio.NioEventLoopGroup;
import io.netty.channel.socket.nio.NioServerSocketChannel;
import io.netty.channel.socket.nio.NioSocketChannel;
import io.netty.handler.codec.*;
import io.netty.handler.codec.bytes.ByteArrayDecoder;
import io.netty.handler.codec.bytes.ByteArrayEncoder;
import io.netty.handler.logging.LogLevel;
import io.netty.handler.logging.LoggingHandler;
import io.netty.util.internal.logging.InternalLoggerFactory;
import io.netty.util.internal.logging.Slf4JLoggerFactory;
import lombok.SneakyThrows;
import lombok.extern.slf4j.Slf4j;
import java.net.InetSocketAddress;
import java.nio.charset.StandardCharsets;
import java.util.List;
@Slf4j
public class ServerMain extends SimpleChannelInboundHandler<ServerMain.ProtocolMessagePojo>
{
public static class ProtocolMessagePojo
{
public String _message;
}
public static class ProtocolEncoderDecoder extends MessageToMessageCodec<byte[], ProtocolMessagePojo>
{
@Override
protected void encode(ChannelHandlerContext _ctx, ProtocolMessagePojo _pojo, List<Object> _list) throws Exception {
_list.add(_pojo._message.getBytes(StandardCharsets.UTF_8));
}
@Override
protected void decode(ChannelHandlerContext _ctx, byte[] _bytes, List<Object> _list) throws Exception {
ProtocolMessagePojo _pojo = new ProtocolMessagePojo();
_pojo._message = new String(_bytes, StandardCharsets.UTF_8);
_list.add(_pojo);
}
}
public static class DelimiterFrameAppender extends MessageToMessageEncoder<ByteBuf>
{
char _a;
public DelimiterFrameAppender(char _a)
{
this._a = _a;
}
@Override
protected void encode(ChannelHandlerContext ctx, ByteBuf msg, List<Object> out) throws Exception
{
int _len = msg.readableBytes()+1;
ByteBuf _buf = ctx.alloc().buffer(_len);
_buf.writeBytes(msg);
_buf.writeByte((byte) this._a);
out.add(_buf);
}
}
static ServerMain _instance;
static Thread _tcpThread;
static int _tcpPort = 56565;
public static void main(String[] args) {
InternalLoggerFactory.setDefaultFactory(new Slf4JLoggerFactory());
_instance = new ServerMain();
_tcpThread = new Thread(_instance::runTcp);
_tcpThread.start();
}
NioEventLoopGroup _tcpEventLoopGroup;
ServerBootstrap _tcpBootstrap;
@SneakyThrows
public void runTcp(){
_tcpEventLoopGroup = new NioEventLoopGroup(Runtime.getRuntime().availableProcessors()*2+1);
try
{
_tcpBootstrap = new ServerBootstrap();
_tcpBootstrap.group(_tcpEventLoopGroup);
_tcpBootstrap.channel(NioServerSocketChannel.class);
_tcpBootstrap.localAddress(new InetSocketAddress(_tcpPort));
_tcpBootstrap.option(ChannelOption.SO_BACKLOG, 128);
_tcpBootstrap.option(ChannelOption.SO_REUSEADDR, true);
_tcpBootstrap.option(ChannelOption.TCP_NODELAY, true);
_tcpBootstrap.childHandler(new ChannelInitializer<NioSocketChannel>() {
protected void initChannel(NioSocketChannel ch) throws Exception
{
ch.pipeline().addLast(new LoggingHandler(LogLevel.WARN));
// server input
//ch.pipeline().addLast(new LengthFieldBasedFrameDecoder(65535, 0, 2, 0, 2));
ch.pipeline().addLast(new DelimiterBasedFrameDecoder(64, true, ch.alloc().buffer(1).writeByte('\n')));
ch.pipeline().addLast(new LoggingHandler(LogLevel.WARN));
ch.pipeline().addLast(new ByteArrayDecoder());
ch.pipeline().addLast(new LoggingHandler(LogLevel.WARN));
// server output
//ch.pipeline().addLast(new LengthFieldPrepender(2));
ch.pipeline().addLast(new DelimiterFrameAppender('\n'));
ch.pipeline().addLast(new ByteArrayEncoder());
ch.pipeline().addLast(new ProtocolEncoderDecoder());
// pojo codec
ch.pipeline().addLast(ServerMain.this);
}
});
ChannelFuture channelFuture = _tcpBootstrap.bind().sync();
}
catch(Exception _e)
{
log.error("ERROR", _e);
}
finally
{
//_tcpEventLoopGroup.shutdownGracefully().sync();
}
}
@Override
protected void channelRead0(ChannelHandlerContext _ctx, ProtocolMessagePojo _pojo) throws Exception
{
log.warn("POJO: "+_pojo._message);
_ctx.channel().write(_pojo);
_ctx.channel().flush();
}
}
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