.github/FUNDING.yml

@@ -0,0 +1 @@
+ko_fi: nanit

README.md

@@ -5,16 +5,16 @@ The main goal of this project is maximum simplicity with a minimum number of sen
 The limbo is empty; there is no ability to set a schematic building since this is not necessary.
 You can send useful information via chat or boss bar.
 
-The server is fully clear. It is only able to keep a lot of players while the main server is down.
+No plugins, no logs. The server is fully clear. It is only able keep a lot of players while the main server is down.
 
 General features:
 * High performance. The server doesn't save or cache any useless (for limbo) data.
-* Doesn't spawn threads per player. Use a fixed thread pool.
+* Doesn't spawn threads per player. Uses a fixed thread pool.
 * Support for **BungeeCord** and **Velocity** info forwarding.
 * Support for [BungeeGuard](https://www.spigotmc.org/resources/79601/) handshake format.
 * Multiple versions support.
 * Fully configurable.
-* Lightweight. App size around **3MB**.
+* Lightweight. App size around **2MB**.
 
 ![](https://i.imgur.com/sT8p1Gz.png)
 
@@ -35,8 +35,7 @@ Symbol `X` means all minor versions.
 - [x] 1.17.X
 - [x] 1.18.X
 - [x] 1.19.X
-- [x] 1.20.X
+- [x] 1.20-1.20.4
-- [x] 1.21
 
 The server **doesn't** support snapshots.
 
@@ -51,16 +50,14 @@ Note that the server also will be closed correctly if you just press `Ctrl+C`.
 
 ### Installation
 
-Required software: JRE 11+
-
 The installation process is simple.
 
 1. Download the latest version of the program [**here**](https://github.com/Nan1t/NanoLimbo/releases).
 2. Put the jar file in the folder you want.
 3. Create a start script as you did for Bukkit or BungeeCord, with a command like this:
    `java -jar NanoLimbo-<version>.jar`
-4. The server will create `settings.yml` file, which is the server configuration. 
+5. The server will create `settings.yml` file, which is the server configuration.
-5. Configure it as you want and restart the server.
+6. Configure it as you want and restart the server.
 
 ### Player info forwarding
 
@@ -78,14 +75,16 @@ Then add your tokens to `tokens` list.
 
 ### Contributing
 
-Feel free to create a pull request if you find some bug or optimization opportunity, or if you want
+Feel free to create a pull request if you found some bug or optimization opportunity, or if you want
 to add some functionality that is suitable for a limbo server and won't significantly load the server.
 
+All PRs should target the `dev` branch to keep the `main` branch stable and clean.
+
 ### Building
 
 Required software:
 
-* JDK 11+
+* JDK 1.8+
 * Gradle 7+ (optional)
 
 To build a minimized jar, go to the project root directory and run in the terminal:

build.gradle

@@ -4,8 +4,8 @@ plugins {
     id 'com.github.gmazzo.buildconfig' version '3.1.0'
 }
 
-group 'ua.nanit'
+group 'ru.nanit'
-version '1.8.1'
+version '1.7'
 
 compileJava {
     options.encoding = "UTF-8"
@@ -24,7 +24,6 @@ dependencies {
     testImplementation 'org.junit.jupiter:junit-jupiter-api:5.9.3'
     testRuntimeOnly 'org.junit.jupiter:junit-jupiter-engine:5.9.3'
 
-    implementation 'ch.qos.logback:logback-classic:1.5.6'
     implementation 'org.spongepowered:configurate-yaml:4.1.2'
     implementation 'io.netty:netty-all:4.1.101.Final'
     implementation 'net.kyori:adventure-nbt:4.14.0'
@@ -45,9 +44,7 @@ shadowJar {
         attributes('Main-Class': 'ua.nanit.limbo.NanoLimbo')
     }
 
-    minimize {
+    minimize()
-        exclude(dependency('ch.qos.logback:logback-classic:.*:.*'))
-    }
 }
 
 test {

src/main/java/ua/nanit/limbo/NanoLimbo.java

@@ -18,7 +18,7 @@
 package ua.nanit.limbo;
 
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 public final class NanoLimbo {
 
@@ -26,7 +26,7 @@ public final class NanoLimbo {
         try {
             new LimboServer().start();
         } catch (Exception e) {
-            Log.error("Cannot start server: ", e);
+            Logger.error("Cannot start server: ", e);
         }
     }
 

src/main/java/ua/nanit/limbo/configuration/LimboConfig.java

@@ -73,8 +73,8 @@ public final class LimboConfig {
 
     private boolean useTrafficLimits;
     private int maxPacketSize;
-    private double interval;
+    private int maxPacketsPerSec;
-    private double maxPacketRate;
+    private int maxBytesPerSec;
 
     public LimboConfig(Path root) {
         this.root = root;
@@ -134,9 +134,9 @@ public final class LimboConfig {
         workerGroupSize = conf.node("netty", "threads", "workerGroup").getInt(4);
 
         useTrafficLimits = conf.node("traffic", "enable").getBoolean(false);
-        maxPacketSize = conf.node("traffic", "maxPacketSize").getInt(-1);
+        maxPacketSize = conf.node("traffic", "packetSize").getInt(-1);
-        interval = conf.node("traffic", "interval").getDouble(-1.0);
+        maxPacketsPerSec = conf.node("traffic", "packets").getInt(-1);
-        maxPacketRate = conf.node("traffic", "maxPacketRate").getDouble(-1.0);
+        maxBytesPerSec = conf.node("traffic", "bytes").getInt(-1);
     }
 
     private BufferedReader getReader() throws IOException {
@@ -269,11 +269,11 @@ public final class LimboConfig {
         return maxPacketSize;
     }
 
-    public double getInterval() {
+    public int getMaxPacketsPerSec() {
-        return interval;
+        return maxPacketsPerSec;
     }
 
-    public double getMaxPacketRate() {
+    public int getMaxBytesPerSec() {
-        return maxPacketRate;
+        return maxBytesPerSec;
     }
 }

src/main/java/ua/nanit/limbo/connection/ClientChannelInitializer.java

@@ -50,8 +50,8 @@ public class ClientChannelInitializer extends ChannelInitializer<Channel> {
         if (server.getConfig().isUseTrafficLimits()) {
             pipeline.addLast("traffic_limit", new ChannelTrafficHandler(
                     server.getConfig().getMaxPacketSize(),
-                    server.getConfig().getInterval(),
+                    server.getConfig().getMaxPacketsPerSec(),
-                    server.getConfig().getMaxPacketRate()
+                    server.getConfig().getMaxBytesPerSec()
             ));
         }
 

src/main/java/ua/nanit/limbo/connection/ClientConnection.java

@@ -36,7 +36,7 @@ import ua.nanit.limbo.protocol.packets.play.PacketKeepAlive;
 import ua.nanit.limbo.protocol.registry.State;
 import ua.nanit.limbo.protocol.registry.Version;
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 import ua.nanit.limbo.util.UuidUtil;
 
 import javax.crypto.Mac;
@@ -104,7 +104,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
     @Override
     public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) {
         if (channel.isActive()) {
-            Log.error("Unhandled exception: ", cause);
+            Logger.error("Unhandled exception: ", cause);
         }
     }
 
@@ -115,7 +115,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
 
     public void handlePacket(Object packet) {
         if (packet instanceof Packet) {
-            ((Packet) packet).handle(this, server);
+            ((Packet)packet).handle(this, server);
         }
     }
 
@@ -199,14 +199,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
 
         if (PacketSnapshots.PACKET_PLUGIN_MESSAGE != null)
             writePacket(PacketSnapshots.PACKET_PLUGIN_MESSAGE);
-
+        writePacket(PacketSnapshots.PACKET_REGISTRY_DATA);
-        if (clientVersion.moreOrEqual(Version.V1_20_5)) {
-            for (PacketSnapshot packet : PacketSnapshots.PACKETS_REGISTRY_DATA) {
-                writePacket(packet);
-            }
-        } else {
-            writePacket(PacketSnapshots.PACKET_REGISTRY_DATA);
-        }
 
         sendPacket(PacketSnapshots.PACKET_FINISH_CONFIGURATION);
     }
@@ -264,6 +257,10 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
         encoder.updateState(state);
     }
 
+    public void updateDecoderState(State state) {
+        decoder.updateState(state);
+    }
+
     public void updateEncoderState(State state) {
         encoder.updateState(state);
     }
@@ -275,7 +272,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
     }
 
     public void setAddress(String host) {
-        this.address = new InetSocketAddress(host, ((InetSocketAddress) this.address).getPort());
+        this.address = new InetSocketAddress(host, ((InetSocketAddress)this.address).getPort());
     }
 
     boolean checkBungeeGuardHandshake(String handshake) {
@@ -312,7 +309,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
         setAddress(socketAddressHostname);
         gameProfile.setUuid(uuid);
 
-        Log.debug("Successfully verified BungeeGuard token");
+        Logger.debug("Successfully verified BungeeGuard token");
 
         return true;
     }
@@ -336,7 +333,7 @@ public class ClientConnection extends ChannelInboundHandlerAdapter {
             byte[] mySignature = mac.doFinal(data);
             if (!MessageDigest.isEqual(signature, mySignature))
                 return false;
-        } catch (InvalidKeyException | java.security.NoSuchAlgorithmException e) {
+        } catch (InvalidKeyException |java.security.NoSuchAlgorithmException e) {
             throw new AssertionError(e);
         }
         int version = buf.readVarInt();

src/main/java/ua/nanit/limbo/connection/PacketHandler.java

@@ -29,7 +29,7 @@ import ua.nanit.limbo.protocol.packets.status.PacketStatusPing;
 import ua.nanit.limbo.protocol.packets.status.PacketStatusRequest;
 import ua.nanit.limbo.protocol.packets.status.PacketStatusResponse;
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 import ua.nanit.limbo.util.UuidUtil;
 
 import java.util.concurrent.ThreadLocalRandom;
@@ -46,7 +46,7 @@ public class PacketHandler {
         conn.updateVersion(packet.getVersion());
         conn.updateState(packet.getNextState());
 
-        Log.debug("Pinged from %s [%s]", conn.getAddress(),
+        Logger.debug("Pinged from %s [%s]", conn.getAddress(),
                 conn.getClientVersion().toString());
 
         if (server.getConfig().getInfoForwarding().isLegacy()) {

src/main/java/ua/nanit/limbo/connection/PacketSnapshots.java

@@ -17,9 +17,6 @@
 
 package ua.nanit.limbo.connection;
 
-import net.kyori.adventure.nbt.BinaryTag;
-import net.kyori.adventure.nbt.CompoundBinaryTag;
-import net.kyori.adventure.nbt.ListBinaryTag;
 import ua.nanit.limbo.LimboConstants;
 import ua.nanit.limbo.protocol.PacketSnapshot;
 import ua.nanit.limbo.protocol.packets.configuration.PacketFinishConfiguration;
@@ -30,7 +27,6 @@ import ua.nanit.limbo.server.LimboServer;
 import ua.nanit.limbo.server.data.Title;
 import ua.nanit.limbo.util.NbtMessageUtil;
 import ua.nanit.limbo.util.UuidUtil;
-import ua.nanit.limbo.world.Dimension;
 
 import java.util.ArrayList;
 import java.util.Collections;
@@ -52,7 +48,7 @@ public final class PacketSnapshots {
     public static PacketSnapshot PACKET_HEADER_AND_FOOTER;
 
     public static PacketSnapshot PACKET_PLAYER_POS_AND_LOOK_LEGACY;
-    // For 1.19 we need to spawn player outside the world to avoid stuck in terrain loading
+    // For 1.19 we need to spawn player outside world to avoid stuck in terrain loading
     public static PacketSnapshot PACKET_PLAYER_POS_AND_LOOK;
 
     public static PacketSnapshot PACKET_TITLE_TITLE;
@@ -64,7 +60,6 @@ public final class PacketSnapshots {
     public static PacketSnapshot PACKET_TITLE_LEGACY_TIMES;
 
     public static PacketSnapshot PACKET_REGISTRY_DATA;
-    public static List<PacketSnapshot> PACKETS_REGISTRY_DATA;
     public static PacketSnapshot PACKET_FINISH_CONFIGURATION;
 
     public static List<PacketSnapshot> PACKETS_EMPTY_CHUNKS;
@@ -198,38 +193,6 @@ public final class PacketSnapshots {
         packetRegistryData.setDimensionRegistry(server.getDimensionRegistry());
 
         PACKET_REGISTRY_DATA = PacketSnapshot.of(packetRegistryData);
-
-        Dimension dimension1_21 = server.getDimensionRegistry().getDimension_1_21();
-        List<PacketSnapshot> packetRegistries = new ArrayList<>();
-        CompoundBinaryTag dimensionTag = dimension1_21.getData();
-        for (String registryType : dimensionTag.keySet()) {
-            CompoundBinaryTag compoundRegistryType = dimensionTag.getCompound(registryType);
-
-            PacketRegistryData registryData = new PacketRegistryData();
-            registryData.setDimensionRegistry(server.getDimensionRegistry());
-
-            ListBinaryTag values = compoundRegistryType.getList("value");
-            registryData.setMetadataWriter((message, version) -> {
-                message.writeString(registryType);
-
-                message.writeVarInt(values.size());
-                for (BinaryTag entry : values) {
-                    CompoundBinaryTag entryTag = (CompoundBinaryTag) entry;
-
-                    String name = entryTag.getString("name");
-                    CompoundBinaryTag element = entryTag.getCompound("element");
-
-                    message.writeString(name);
-                    message.writeBoolean(true);
-                    message.writeNamelessCompoundTag(element);
-                }
-            });
-
-            packetRegistries.add(PacketSnapshot.of(registryData));
-        }
-
-        PACKETS_REGISTRY_DATA = packetRegistries;
-
         PACKET_FINISH_CONFIGURATION = PacketSnapshot.of(new PacketFinishConfiguration());
 
         PacketGameEvent packetGameEvent = new PacketGameEvent();

src/main/java/ua/nanit/limbo/connection/pipeline/ChannelTrafficHandler.java

@@ -4,20 +4,23 @@ import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.channel.ChannelInboundHandlerAdapter;
 import org.jetbrains.annotations.NotNull;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
-
-import java.util.Arrays;
 
 public class ChannelTrafficHandler extends ChannelInboundHandlerAdapter {
 
-    private final int maxPacketSize;
+    private final int packetSize;
-    private final double maxPacketRate;
+    private final int packetsPerSec;
-    private final PacketBucket packetBucket;
+    private final int bytesPerSec;
 
-    public ChannelTrafficHandler(int maxPacketSize, double interval, double maxPacketRate) {
+    private int packetsCounter;
-        this.maxPacketSize = maxPacketSize;
+    private int bytesCounter;
-        this.maxPacketRate = maxPacketRate;
+
-        this.packetBucket = (interval > 0.0 && maxPacketRate > 0.0) ? new PacketBucket(interval * 1000.0, 150) : null;
+    private long lastPacket;
+
+    public ChannelTrafficHandler(int packetSize, int packetsPerSec, int bytesPerSec) {
+        this.packetSize = packetSize;
+        this.packetsPerSec = packetsPerSec;
+        this.bytesPerSec = bytesPerSec;
     }
 
     @Override
@@ -26,86 +29,47 @@ public class ChannelTrafficHandler extends ChannelInboundHandlerAdapter {
             ByteBuf in = (ByteBuf) msg;
             int bytes = in.readableBytes();
 
-            if (maxPacketSize > 0 && bytes > maxPacketSize) {
+            if (packetSize > 0 && bytes > packetSize) {
-                closeConnection(ctx, "Closed %s due to large packet size (%d bytes)", ctx.channel().remoteAddress(), bytes);
+                closeConnection(ctx, "Closed %s due too large packet size (%d bytes)", ctx.channel().remoteAddress(), bytes);
                 return;
             }
 
-            if (packetBucket != null) {
+            if (!measureTraffic(ctx, bytes)) return;
-                packetBucket.incrementPackets(1);
-                if (packetBucket.getCurrentPacketRate() > maxPacketRate) {
-                    closeConnection(ctx, "Closed %s due to many packets sent (%d in the last %.1f seconds)", ctx.channel().remoteAddress(), packetBucket.sum, (packetBucket.intervalTime / 1000.0));
-                    return;
-                }
-            }
         }
 
         super.channelRead(ctx, msg);
     }
 
+    private boolean measureTraffic(ChannelHandlerContext ctx, int bytes) {
+        if (packetsPerSec < 0 && bytesPerSec < 0) return true;
+
+        long time = System.currentTimeMillis();
+
+        if (time - lastPacket >= 1000) {
+            bytesCounter = 0;
+            packetsCounter = 0;
+        }
+
+        packetsCounter++;
+        bytesCounter += bytes;
+
+        if (packetsPerSec > 0 && packetsCounter > packetsPerSec) {
+            closeConnection(ctx, "Closed %s due too frequent packet sending (%d per sec)", ctx.channel().remoteAddress(), packetsCounter);
+            return false;
+        }
+
+        if (bytesPerSec > 0 && bytesCounter > bytesPerSec) {
+            closeConnection(ctx, "Closed %s due too many bytes sent per second (%d per sec)", ctx.channel().remoteAddress(), bytesCounter);
+            return false;
+        }
+
+        lastPacket = time;
+
+        return true;
+    }
+
     private void closeConnection(ChannelHandlerContext ctx, String reason, Object... args) {
         ctx.close();
-        Log.info(reason, args);
+        Logger.info(reason, args);
-    }
-
-    private static class PacketBucket {
-        private static final double NANOSECONDS_TO_MILLISECONDS = 1.0e-6;
-        private static final int MILLISECONDS_TO_SECONDS = 1000;
-
-        private final double intervalTime;
-        private final double intervalResolution;
-        private final int[] data;
-        private int newestData;
-        private double lastBucketTime;
-        private int sum;
-
-        public PacketBucket(final double intervalTime, final int totalBuckets) {
-            this.intervalTime = intervalTime;
-            this.intervalResolution = intervalTime / totalBuckets;
-            this.data = new int[totalBuckets];
-        }
-
-        public void incrementPackets(final int packets) {
-            double timeMs = System.nanoTime() * NANOSECONDS_TO_MILLISECONDS;
-            double timeDelta = timeMs - this.lastBucketTime;
-
-            if (timeDelta < 0.0) {
-                timeDelta = 0.0;
-            }
-
-            if (timeDelta < this.intervalResolution) {
-                this.data[this.newestData] += packets;
-                this.sum += packets;
-                return;
-            }
-
-            int bucketsToMove = (int)(timeDelta / this.intervalResolution);
-            double nextBucketTime = this.lastBucketTime + bucketsToMove * this.intervalResolution;
-
-            if (bucketsToMove >= this.data.length) {
-                Arrays.fill(this.data, 0);
-                this.data[0] = packets;
-                this.sum = packets;
-                this.newestData = 0;
-                this.lastBucketTime = timeMs;
-                return;
-            }
-
-            for (int i = 1; i < bucketsToMove; ++i) {
-                int index = (this.newestData + i) % this.data.length;
-                this.sum -= this.data[index];
-                this.data[index] = 0;
-            }
-
-            int newestDataIndex = (this.newestData + bucketsToMove) % this.data.length;
-            this.sum += packets - this.data[newestDataIndex];
-            this.data[newestDataIndex] = packets;
-            this.newestData = newestDataIndex;
-            this.lastBucketTime = nextBucketTime;
-        }
-
-        public double getCurrentPacketRate() {
-            return this.sum / (this.intervalTime / MILLISECONDS_TO_SECONDS);
-        }
     }
 }

src/main/java/ua/nanit/limbo/connection/pipeline/PacketDecoder.java

@@ -24,7 +24,7 @@ import ua.nanit.limbo.protocol.ByteMessage;
 import ua.nanit.limbo.protocol.Packet;
 import ua.nanit.limbo.protocol.registry.State;
 import ua.nanit.limbo.protocol.registry.Version;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 import java.util.List;
 
@@ -47,20 +47,22 @@ public class PacketDecoder extends MessageToMessageDecoder<ByteBuf> {
         Packet packet = mappings.getPacket(packetId);
 
         if (packet != null) {
-            Log.debug("Received packet %s[0x%s] (%d bytes)", packet.toString(), Integer.toHexString(packetId), msg.readableBytes());
+            Logger.debug("Received packet %s[0x%s] (%d bytes)", packet.toString(), Integer.toHexString(packetId), msg.readableBytes());
             try {
                 packet.decode(msg, version);
             } catch (Exception e) {
-                if (Log.isDebug()) {
+                if (Logger.isDebug()) {
-                    Log.warning("Cannot decode packet 0x%s", e, Integer.toHexString(packetId));
+                    Logger.warning("Cannot decode packet 0x%s", Integer.toHexString(packetId));
-                } else {
+                    e.printStackTrace();
-                    Log.warning("Cannot decode packet 0x%s: %s", Integer.toHexString(packetId), e.getMessage());
+                }
+                else {
+                    Logger.warning("Cannot decode packet 0x%s: %s", Integer.toHexString(packetId), e.getMessage());
                 }
             }
 
             ctx.fireChannelRead(packet);
         } else {
-            Log.debug("Undefined incoming packet: 0x" + Integer.toHexString(packetId));
+            Logger.debug("Undefined incoming packet: 0x" + Integer.toHexString(packetId));
         }
     }
 

src/main/java/ua/nanit/limbo/connection/pipeline/PacketEncoder.java

@@ -25,7 +25,7 @@ import ua.nanit.limbo.protocol.Packet;
 import ua.nanit.limbo.protocol.PacketSnapshot;
 import ua.nanit.limbo.protocol.registry.State;
 import ua.nanit.limbo.protocol.registry.Version;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 public class PacketEncoder extends MessageToByteEncoder<Packet> {
 
@@ -51,7 +51,7 @@ public class PacketEncoder extends MessageToByteEncoder<Packet> {
         }
 
         if (packetId == -1) {
-            Log.warning("Undefined packet class: %s[0x%s] (%d bytes)", packet.getClass().getName(), Integer.toHexString(packetId), msg.readableBytes());
+            Logger.warning("Undefined packet class: %s[0x%s] (%d bytes)", packet.getClass().getName(), Integer.toHexString(packetId), msg.readableBytes());
             return;
         }
 
@@ -60,11 +60,11 @@ public class PacketEncoder extends MessageToByteEncoder<Packet> {
         try {
             packet.encode(msg, version);
 
-            if (Log.isDebug()) {
+            if (Logger.getLevel() >= Logger.Level.DEBUG.getIndex()) {
-                Log.debug("Sending %s[0x%s] packet (%d bytes)", packet.toString(), Integer.toHexString(packetId), msg.readableBytes());
+                Logger.debug("Sending %s[0x%s] packet (%d bytes)", packet.toString(), Integer.toHexString(packetId), msg.readableBytes());
             }
         } catch (Exception e) {
-            Log.error("Cannot encode packet 0x%s: %s", Integer.toHexString(packetId), e.getMessage());
+            Logger.error("Cannot encode packet 0x%s: %s", Integer.toHexString(packetId), e.getMessage());
         }
     }
 

src/main/java/ua/nanit/limbo/connection/pipeline/VarIntFrameDecoder.java

@@ -20,7 +20,7 @@ package ua.nanit.limbo.connection.pipeline;
 import io.netty.buffer.ByteBuf;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.handler.codec.ByteToMessageDecoder;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 import java.util.List;
 
@@ -42,7 +42,7 @@ public class VarIntFrameDecoder extends ByteToMessageDecoder {
             int readVarInt = reader.getReadVarInt();
             int bytesRead = reader.getBytesRead();
             if (readVarInt < 0) {
-                Log.error("[VarIntFrameDecoder] Bad data length");
+                Logger.error("[VarIntFrameDecoder] Bad data length");
             } else if (readVarInt == 0) {
                 in.readerIndex(varIntEnd + 1);
             } else {
@@ -54,7 +54,7 @@ public class VarIntFrameDecoder extends ByteToMessageDecoder {
                 }
             }
         } else if (reader.getResult() == VarIntByteDecoder.DecodeResult.TOO_BIG) {
-            Log.error("[VarIntFrameDecoder] Too big data");
+            Logger.error("[VarIntFrameDecoder] Too big data");
         }
     }
 }

src/main/java/ua/nanit/limbo/protocol/ByteMessage.java

@@ -73,37 +73,14 @@ public class ByteMessage extends ByteBuf {
     }
 
     public void writeVarInt(int value) {
-        // Peel the one and two byte count cases explicitly as they are the most common VarInt sizes
+        while (true) {
-        // that the proxy will write, to improve inlining.
+            if ((value & 0xFFFFFF80) == 0) {
-        if ((value & (0xFFFFFFFF << 7)) == 0) {
+                buf.writeByte(value);
-            buf.writeByte(value);
+                return;
-        } else if ((value & (0xFFFFFFFF << 14)) == 0) {
+            }
-            int w = (value & 0x7F | 0x80) << 8 | (value >>> 7);
-            buf.writeShort(w);
-        } else {
-            writeVarIntFull(value);
-        }
-    }
 
-    private void writeVarIntFull(final int value) {
+            buf.writeByte(value & 0x7F | 0x80);
-        // See https://steinborn.me/posts/performance/how-fast-can-you-write-a-varint/
+            value >>>= 7;
-        if ((value & (0xFFFFFFFF << 7)) == 0) {
-            buf.writeByte(value);
-        } else if ((value & (0xFFFFFFFF << 14)) == 0) {
-            int w = (value & 0x7F | 0x80) << 8 | (value >>> 7);
-            buf.writeShort(w);
-        } else if ((value & (0xFFFFFFFF << 21)) == 0) {
-            int w = (value & 0x7F | 0x80) << 16 | ((value >>> 7) & 0x7F | 0x80) << 8 | (value >>> 14);
-            buf.writeMedium(w);
-        } else if ((value & (0xFFFFFFFF << 28)) == 0) {
-            int w = (value & 0x7F | 0x80) << 24 | (((value >>> 7) & 0x7F | 0x80) << 16)
-                    | ((value >>> 14) & 0x7F | 0x80) << 8 | (value >>> 21);
-            buf.writeInt(w);
-        } else {
-            int w = (value & 0x7F | 0x80) << 24 | ((value >>> 7) & 0x7F | 0x80) << 16
-                    | ((value >>> 14) & 0x7F | 0x80) << 8 | ((value >>> 21) & 0x7F | 0x80);
-            buf.writeInt(w);
-            buf.writeByte(value >>> 28);
         }
     }
 

src/main/java/ua/nanit/limbo/protocol/MetadataWriter.java

@@ -1,10 +0,0 @@
-package ua.nanit.limbo.protocol;
-
-import ua.nanit.limbo.protocol.registry.Version;
-
-@FunctionalInterface
-public interface MetadataWriter {
-
-    void writeData(ByteMessage message, Version version);
-
-}

src/main/java/ua/nanit/limbo/protocol/PacketSnapshot.java

@@ -23,8 +23,8 @@ import java.util.HashMap;
 import java.util.Map;
 
 /**
- * PacketSnapshot encodes a packet to byte array for each MC version.
+ * PacketSnapshot encodes packet to byte array for each MC version.
- * Some versions have the same snapshot, so there are mappings to avoid data copying
+ * Some versions have same snapshot, so there are mappings to avoid data copying
  */
 public class PacketSnapshot implements PacketOut {
 

src/main/java/ua/nanit/limbo/protocol/packets/configuration/PacketRegistryData.java

@@ -1,7 +1,6 @@
 package ua.nanit.limbo.protocol.packets.configuration;
 
 import ua.nanit.limbo.protocol.ByteMessage;
-import ua.nanit.limbo.protocol.MetadataWriter;
 import ua.nanit.limbo.protocol.PacketOut;
 import ua.nanit.limbo.protocol.registry.Version;
 import ua.nanit.limbo.world.DimensionRegistry;
@@ -9,24 +8,13 @@ import ua.nanit.limbo.world.DimensionRegistry;
 public class PacketRegistryData implements PacketOut {
 
     private DimensionRegistry dimensionRegistry;
-    private MetadataWriter metadataWriter;
 
     public void setDimensionRegistry(DimensionRegistry dimensionRegistry) {
         this.dimensionRegistry = dimensionRegistry;
     }
 
-    public void setMetadataWriter(MetadataWriter metadataWriter) {
-        this.metadataWriter = metadataWriter;
-    }
-
     @Override
     public void encode(ByteMessage msg, Version version) {
-        if (metadataWriter != null) {
-            if (version.moreOrEqual(Version.V1_20_5)) {
-                metadataWriter.writeData(msg, version);
-                return;
-            }
-        }
         msg.writeNamelessCompoundTag(dimensionRegistry.getCodec_1_20());
     }
 }

src/main/java/ua/nanit/limbo/protocol/packets/login/PacketLoginSuccess.java

@@ -49,9 +49,6 @@ public class PacketLoginSuccess implements PacketOut {
         if (version.moreOrEqual(Version.V1_19)) {
             msg.writeVarInt(0);
         }
-        if (version.moreOrEqual(Version.V1_20_5)) {
-            msg.writeBoolean(true);
-        }
     }
 
     @Override

src/main/java/ua/nanit/limbo/protocol/packets/play/PacketJoinGame.java

@@ -39,7 +39,6 @@ public class PacketJoinGame implements PacketOut {
     private boolean isDebug;
     private boolean isFlat;
     private boolean limitedCrafting;
-    private boolean secureProfile;
 
     public void setEntityId(int entityId) {
         this.entityId = entityId;
@@ -101,10 +100,6 @@ public class PacketJoinGame implements PacketOut {
         this.limitedCrafting = limitedCrafting;
     }
 
-    public void setSecureProfile(boolean secureProfile) {
-        this.secureProfile = secureProfile;
-    }
-
     @Override
     public void encode(ByteMessage msg, Version version) {
         msg.writeInt(entityId);
@@ -260,7 +255,7 @@ public class PacketJoinGame implements PacketOut {
             msg.writeVarInt(0);
         }
 
-        if (version.fromTo(Version.V1_20_2, Version.V1_20_3)) {
+        if (version.moreOrEqual(Version.V1_20_2)) {
             msg.writeBoolean(isHardcore);
             msg.writeStringsArray(worldNames);
             msg.writeVarInt(maxPlayers);
@@ -279,27 +274,6 @@ public class PacketJoinGame implements PacketOut {
             msg.writeBoolean(false);
             msg.writeVarInt(0);
         }
-
-        if (version.moreOrEqual(Version.V1_20_5)) {
-            msg.writeBoolean(isHardcore);
-            msg.writeStringsArray(worldNames);
-            msg.writeVarInt(maxPlayers);
-            msg.writeVarInt(viewDistance);
-            msg.writeVarInt(viewDistance); // Simulation Distance
-            msg.writeBoolean(reducedDebugInfo);
-            msg.writeBoolean(enableRespawnScreen);
-            msg.writeBoolean(limitedCrafting);
-            msg.writeVarInt(dimensionRegistry.getDimension_1_20_5().getId());
-            msg.writeString(worldName);
-            msg.writeLong(hashedSeed);
-            msg.writeByte(gameMode);
-            msg.writeByte(previousGameMode);
-            msg.writeBoolean(isDebug);
-            msg.writeBoolean(isFlat);
-            msg.writeBoolean(false);
-            msg.writeVarInt(0);
-            msg.writeBoolean(secureProfile);
-        }
     }
 
 }

src/main/java/ua/nanit/limbo/protocol/registry/State.java

@@ -66,7 +66,7 @@ public enum State {
             );
             serverBound.register(
                     PacketLoginAcknowledged::new,
-                    map(0x03, V1_20_2, Version.getMax())
+                    map(0x03, V1_20_2, V1_20_3)
             );
             clientBound.register(PacketDisconnect::new,
                     map(0x00, Version.getMin(), Version.getMax())
@@ -83,44 +83,36 @@ public enum State {
         {
             clientBound.register(
                     PacketPluginMessage::new,
-                    map(0x00, V1_20_2, V1_20_3),
+                    map(0x00, V1_20_2, V1_20_3)
-                    map(0x01, V1_20_5, V1_21)
             );
             clientBound.register(
                     PacketDisconnect::new,
-                    map(0x01, V1_20_2, V1_20_3),
+                    map(0x01, V1_20_2, V1_20_3)
-                    map(0x02, V1_20_5, V1_21)
             );
             clientBound.register(
                     PacketFinishConfiguration::new,
-                    map(0x02, V1_20_2, V1_20_3),
+                    map(0x02, V1_20_2, V1_20_3)
-                    map(0x03, V1_20_5, V1_21)
             );
             clientBound.register(
                     PacketKeepAlive::new,
-                    map(0x03, V1_20_2, V1_20_3),
+                    map(0x03, V1_20_2, V1_20_3)
-                    map(0x04, V1_20_5, V1_21)
             );
             clientBound.register(
                     PacketRegistryData::new,
-                    map(0x05, V1_20_2, V1_20_3),
+                    map(0x05, V1_20_2, V1_20_3)
-                    map(0x07, V1_20_5, V1_21)
             );
 
             serverBound.register(
                     PacketPluginMessage::new,
-                    map(0x01, V1_20_2, V1_20_3),
+                    map(0x01, V1_20_2, V1_20_3)
-                    map(0x02, V1_20_2, V1_21)
             );
             serverBound.register(
                     PacketFinishConfiguration::new,
-                    map(0x02, V1_20_2, V1_20_3),
+                    map(0x02, V1_20_2, V1_20_3)
-                    map(0x03, V1_20_5, V1_21)
             );
             serverBound.register(
                     PacketKeepAlive::new,
-                    map(0x03, V1_20_2, V1_20_3),
+                    map(0x03, V1_20_2, V1_20_3)
-                    map(0x04, V1_20_5, V1_21)
             );
         }
     },
@@ -140,8 +132,7 @@ public enum State {
                     map(0x11, V1_19_3, V1_19_3),
                     map(0x12, V1_19_4, V1_20),
                     map(0x14, V1_20_2, V1_20_2),
-                    map(0x15, V1_20_3, V1_20_3),
+                    map(0x15, V1_20_3, V1_20_3)
-                    map(0x18, V1_20_5, V1_21)
             );
 
             clientBound.register(PacketDeclareCommands::new,
@@ -153,7 +144,7 @@ public enum State {
                     map(0x0F, V1_19, V1_19_1),
                     map(0x0E, V1_19_3, V1_19_3),
                     map(0x10, V1_19_4, V1_20),
-                    map(0x11, V1_20_2, V1_21)
+                    map(0x11, V1_20_2, V1_20_3)
             );
             clientBound.register(PacketJoinGame::new,
                     map(0x01, V1_7_2, V1_8),
@@ -167,8 +158,7 @@ public enum State {
                     map(0x25, V1_19_1, V1_19_1),
                     map(0x24, V1_19_3, V1_19_3),
                     map(0x28, V1_19_4, V1_20),
-                    map(0x29, V1_20_2, V1_20_3),
+                    map(0x29, V1_20_2, V1_20_3)
-                    map(0x2B, V1_20_5, V1_21)
             );
             clientBound.register(PacketPluginMessage::new,
                     map(0x19, V1_13, V1_13_2),
@@ -181,8 +171,7 @@ public enum State {
                     map(0x16, V1_19_1, V1_19_1),
                     map(0x15, V1_19_3, V1_19_3),
                     map(0x17, V1_19_4, V1_20),
-                    map(0x18, V1_20_2, V1_20_3),
+                    map(0x18, V1_20_2, V1_20_3)
-                    map(0x19, V1_20_5, V1_21)
             );
             clientBound.register(PacketPlayerAbilities::new,
                     map(0x39, V1_7_2, V1_8),
@@ -198,8 +187,7 @@ public enum State {
                     map(0x31, V1_19_1, V1_19_1),
                     map(0x30, V1_19_3, V1_19_3),
                     map(0x34, V1_19_4, V1_20),
-                    map(0x36, V1_20_2, V1_20_3),
+                    map(0x36, V1_20_2, V1_20_3)
-                    map(0x38, V1_20_5, V1_21)
             );
             clientBound.register(PacketPlayerPositionAndLook::new,
                     map(0x08, V1_7_2, V1_8),
@@ -215,8 +203,7 @@ public enum State {
                     map(0x39, V1_19_1, V1_19_1),
                     map(0x38, V1_19_3, V1_19_3),
                     map(0x3C, V1_19_4, V1_20),
-                    map(0x3E, V1_20_2, V1_20_3),
+                    map(0x3E, V1_20_2, V1_20_3)
-                    map(0x40, V1_20_5, V1_21)
             );
             clientBound.register(PacketKeepAlive::new,
                     map(0x00, V1_7_2, V1_8),
@@ -231,8 +218,7 @@ public enum State {
                     map(0x20, V1_19_1, V1_19_1),
                     map(0x1F, V1_19_3, V1_19_3),
                     map(0x23, V1_19_4, V1_20),
-                    map(0x24, V1_20_2, V1_20_3),
+                    map(0x24, V1_20_2, V1_20_3)
-                    map(0x26, V1_20_5, V1_21)
             );
             clientBound.register(PacketChatMessage::new,
                     map(0x02, V1_7_2, V1_8),
@@ -246,8 +232,7 @@ public enum State {
                     map(0x60, V1_19_3, V1_19_3),
                     map(0x64, V1_19_4, V1_20),
                     map(0x67, V1_20_2, V1_20_2),
-                    map(0x69, V1_20_3, V1_20_3),
+                    map(0x69, V1_20_3, V1_20_3)
-                    map(0x6C, V1_20_5, V1_21)
             );
             clientBound.register(PacketBossBar::new,
                     map(0x0C, V1_9, V1_14_4),
@@ -256,7 +241,7 @@ public enum State {
                     map(0x0D, V1_17, V1_18_2),
                     map(0x0A, V1_19, V1_19_3),
                     map(0x0B, V1_19_4, V1_20),
-                    map(0x0A, V1_20_2, V1_21)
+                    map(0x0A, V1_20_2, V1_20_3)
             );
             clientBound.register(PacketPlayerInfo::new,
                     map(0x38, V1_7_2, V1_8),
@@ -272,8 +257,7 @@ public enum State {
                     map(0x37, V1_19_1, V1_19_1),
                     map(0x36, V1_19_3, V1_19_3),
                     map(0x3A, V1_19_4, V1_20),
-                    map(0x3C, V1_20_2, V1_20_3),
+                    map(0x3C, V1_20_2, V1_20_3)
-                    map(0x3E, V1_20_5, V1_21)
             );
             clientBound.register(PacketTitleLegacy::new,
                     map(0x45, V1_8, V1_11_1),
@@ -291,8 +275,7 @@ public enum State {
                     map(0x5B, V1_19_3, V1_19_3),
                     map(0x5F, V1_19_4, V1_20),
                     map(0x61, V1_20_2, V1_20_2),
-                    map(0x63, V1_20_3, V1_20_3),
+                    map(0x63, V1_20_3, V1_20_3)
-                    map(0x65, V1_20_5, V1_21)
             );
             clientBound.register(PacketTitleSetSubTitle::new,
                     map(0x57, V1_17, V1_17_1),
@@ -301,8 +284,7 @@ public enum State {
                     map(0x59, V1_19_3, V1_19_3),
                     map(0x5D, V1_19_4, V1_20),
                     map(0x5F, V1_20_2, V1_20_2),
-                    map(0x61, V1_20_3, V1_20_3),
+                    map(0x61, V1_20_3, V1_20_3)
-                    map(0x63, V1_20_5, V1_21)
             );
             clientBound.register(PacketTitleTimes::new,
                     map(0x5A, V1_17, V1_17_1),
@@ -311,8 +293,7 @@ public enum State {
                     map(0x5C, V1_19_3, V1_19_3),
                     map(0x60, V1_19_4, V1_20),
                     map(0x62, V1_20_2, V1_20_2),
-                    map(0x64, V1_20_3, V1_20_3),
+                    map(0x64, V1_20_3, V1_20_3)
-                    map(0x66, V1_20_5, V1_21)
             );
             clientBound.register(PacketPlayerListHeader::new,
                     map(0x47, V1_8, V1_8),
@@ -331,23 +312,19 @@ public enum State {
                     map(0x61, V1_19_3, V1_19_3),
                     map(0x65, V1_19_4, V1_20),
                     map(0x68, V1_20_2, V1_20_2),
-                    map(0x6A, V1_20_3, V1_20_3),
+                    map(0x6A, V1_20_3, V1_20_3)
-                    map(0x6D, V1_20_5, V1_21)
             );
             clientBound.register(PacketSpawnPosition::new,
                     map(0x4C, V1_19_3, V1_19_3),
                     map(0x50, V1_19_4, V1_20),
                     map(0x52, V1_20_2, V1_20_2),
-                    map(0x54, V1_20_3, V1_20_3),
+                    map(0x54, V1_20_3, V1_20_3)
-                    map(0x56, V1_20_5, V1_21)
             );
             clientBound.register(PacketGameEvent::new,
-                    map(0x20, V1_20_3, V1_20_3),
+                    map(0x20, V1_20_3, V1_20_3)
-                    map(0x22, V1_20_5, V1_21)
             );
             clientBound.register(PacketEmptyChunk::new,
-                    map(0x25, V1_20_3, V1_20_3),
+                    map(0x25, V1_20_3, V1_20_3)
-                    map(0x27, V1_20_5, V1_21)
             );
         }
     };

src/main/java/ua/nanit/limbo/protocol/registry/Version.java

@@ -71,10 +71,7 @@ public enum Version {
     V1_20(763),
     // 1.20.1 has same protocol number
     V1_20_2(764),
-    V1_20_3(765),
+    V1_20_3(765);
-    V1_20_5(766),
-    // 1.20.6 has same protocol number
-    V1_21(767);
 
     private static final Map<Integer, Version> VERSION_MAP;
     private static final Version MAX;

src/main/java/ua/nanit/limbo/server/CommandManager.java

@@ -40,12 +40,12 @@ public final class CommandManager extends Thread {
                 try {
                     handler.execute();
                 } catch (Throwable t) {
-                    Log.error("Cannot execute command:", t);
+                    Logger.error("Cannot execute command:", t);
                 }
                 continue;
             }
 
-            Log.info("Unknown command. Type \"help\" to get commands list");
+            Logger.info("Unknown command. Type \"help\" to get commands list");
         }
     }
 

src/main/java/ua/nanit/limbo/server/Connections.java

@@ -43,12 +43,12 @@ public final class Connections {
 
     public void addConnection(ClientConnection connection) {
         connections.put(connection.getUuid(), connection);
-        Log.info("Player %s connected (%s) [%s]", connection.getUsername(),
+        Logger.info("Player %s connected (%s) [%s]", connection.getUsername(),
                 connection.getAddress(), connection.getClientVersion());
     }
 
     public void removeConnection(ClientConnection connection) {
         connections.remove(connection.getUuid());
-        Log.info("Player %s disconnected", connection.getUsername());
+        Logger.info("Player %s disconnected", connection.getUsername());
     }
 }

src/main/java/ua/nanit/limbo/server/LimboServer.java

@@ -72,14 +72,13 @@ public final class LimboServer {
     }
 
     public void start() throws Exception {
-        config = new LimboConfig(Paths.get("./"));
+        Logger.info("Starting server...");
-        config.load();
-
-        Log.setLevel(config.getDebugLevel());
-        Log.info("Starting server...");
 
         ResourceLeakDetector.setLevel(ResourceLeakDetector.Level.DISABLED);
 
+        config = new LimboConfig(Paths.get("./"));
+        config.load();
+
         packetHandler = new PacketHandler(this);
         dimensionRegistry = new DimensionRegistry(this);
         dimensionRegistry.load(config.getDimensionType());
@@ -93,7 +92,9 @@ public final class LimboServer {
 
         Runtime.getRuntime().addShutdownHook(new Thread(this::stop, "NanoLimbo shutdown thread"));
 
-        Log.info("Server started on %s", config.getAddress());
+        Logger.info("Server started on %s", config.getAddress());
+
+        Logger.setLevel(config.getDebugLevel());
 
         commandManager = new CommandManager();
         commandManager.registerAll(this);
@@ -109,12 +110,12 @@ public final class LimboServer {
             bossGroup = new EpollEventLoopGroup(config.getBossGroupSize());
             workerGroup = new EpollEventLoopGroup(config.getWorkerGroupSize());
             channelClass = EpollServerSocketChannel.class;
-            Log.debug("Using Epoll transport type");
+            Logger.debug("Using Epoll transport type");
         } else {
             bossGroup = new NioEventLoopGroup(config.getBossGroupSize());
             workerGroup = new NioEventLoopGroup(config.getWorkerGroupSize());
             channelClass = NioServerSocketChannel.class;
-            Log.debug("Using Java NIO transport type");
+            Logger.debug("Using Java NIO transport type");
         }
 
         new ServerBootstrap()
@@ -131,7 +132,7 @@ public final class LimboServer {
     }
 
     private void stop() {
-        Log.info("Stopping server...");
+        Logger.info("Stopping server...");
 
         if (keepAliveTask != null) {
             keepAliveTask.cancel(true);
@@ -145,7 +146,7 @@ public final class LimboServer {
             workerGroup.shutdownGracefully();
         }
 
-        Log.info("Server stopped, Goodbye!");
+        Logger.info("Server stopped, Goodbye!");
     }
 
 }

src/main/java/ua/nanit/limbo/server/Logger.java

@@ -17,71 +17,65 @@
 
 package ua.nanit.limbo.server;
 
-import ch.qos.logback.classic.Logger;
+import java.time.LocalTime;
-import org.slf4j.LoggerFactory;
+import java.time.format.DateTimeFormatter;
 
-public final class Log {
+public final class Logger {
 
-    private static final Logger LOGGER = (Logger) LoggerFactory.getLogger("Limbo");
+    private static final DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("hh:mm:ss");
     private static int debugLevel = Level.INFO.getIndex();
 
-    private Log() {}
+    private Logger() {}
+
+    public static int getLevel() {
+        return debugLevel;
+    }
 
     public static void info(Object msg, Object... args) {
-        LOGGER.info(String.format(msg.toString(), args));
+        print(Level.INFO, msg, null, args);
     }
 
     public static void debug(Object msg, Object... args) {
-        LOGGER.debug(String.format(msg.toString(), args));
+        print(Level.DEBUG, msg, null, args);
     }
 
     public static void warning(Object msg, Object... args) {
-        LOGGER.warn(String.format(msg.toString(), args));
+        print(Level.WARNING, msg, null, args);
     }
 
     public static void warning(Object msg, Throwable t, Object... args) {
-        LOGGER.warn(String.format(msg.toString(), args), t);
+        print(Level.WARNING, msg, t, args);
     }
 
     public static void error(Object msg, Object... args) {
-        LOGGER.error(msg.toString(), args);
+        print(Level.ERROR, msg, null, args);
     }
 
     public static void error(Object msg, Throwable t, Object... args) {
-        LOGGER.error(String.format(msg.toString(), args), t);
+        print(Level.ERROR, msg, t, args);
+    }
+
+    public static void print(Level level, Object msg, Throwable t, Object... args) {
+        if (debugLevel >= level.getIndex()) {
+            System.out.printf("%s: %s%n", getPrefix(level), String.format(msg.toString(), args));
+            if (t != null) t.printStackTrace();
+        }
     }
 
     public static boolean isDebug() {
         return debugLevel >= Level.DEBUG.getIndex();
     }
 
+    private static String getPrefix(Level level) {
+        return String.format("[%s] [%s]", getTime(), level.getDisplay());
+    }
+
+    private static String getTime() {
+        return LocalTime.now().format(FORMATTER);
+    }
+
     static void setLevel(int level) {
         debugLevel = level;
-
-        Logger logback = getRootLogger();
-
-        if (logback != null) {
-            logback.setLevel(convertLevel(level));
-        }
-    }
-
-    private static Logger getRootLogger() {
-        return (Logger) LoggerFactory.getLogger(org.slf4j.Logger.ROOT_LOGGER_NAME);
-    }
-
-    private static ch.qos.logback.classic.Level convertLevel(int level) {
-        switch (level) {
-            case 0:
-                return ch.qos.logback.classic.Level.ERROR;
-            case 1:
-                return ch.qos.logback.classic.Level.WARN;
-            case 2:
-                return ch.qos.logback.classic.Level.INFO;
-            case 3:
-                return ch.qos.logback.classic.Level.DEBUG;
-            default:
-                throw new IllegalStateException("Undefined log level: " + level);
-        }
     }
 
     public enum Level {

src/main/java/ua/nanit/limbo/server/commands/CmdConn.java

@@ -2,7 +2,7 @@ package ua.nanit.limbo.server.commands;
 
 import ua.nanit.limbo.server.Command;
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 public class CmdConn implements Command {
 
@@ -14,7 +14,7 @@ public class CmdConn implements Command {
 
     @Override
     public void execute() {
-        Log.info("Connections: %d", server.getConnections().getCount());
+        Logger.info("Connections: %d", server.getConnections().getCount());
     }
 
     @Override

src/main/java/ua/nanit/limbo/server/commands/CmdHelp.java

@@ -2,7 +2,7 @@ package ua.nanit.limbo.server.commands;
 
 import ua.nanit.limbo.server.Command;
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 import java.util.Map;
 
@@ -18,10 +18,10 @@ public class CmdHelp implements Command {
     public void execute() {
         Map<String, Command> commands = server.getCommandManager().getCommands();
 
-        Log.info("Available commands:");
+        Logger.info("Available commands:");
 
         for (Map.Entry<String, Command> entry : commands.entrySet()) {
-            Log.info("%s - %s", entry.getKey(), entry.getValue().description());
+            Logger.info("%s - %s", entry.getKey(), entry.getValue().description());
         }
     }
 

src/main/java/ua/nanit/limbo/server/commands/CmdMem.java

@@ -1,7 +1,7 @@
 package ua.nanit.limbo.server.commands;
 
 import ua.nanit.limbo.server.Command;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 public class CmdMem implements Command {
 
@@ -14,11 +14,11 @@ public class CmdMem implements Command {
         long free = runtime.freeMemory() / mb;
         long max = runtime.maxMemory() / mb;
 
-        Log.info("Memory usage:");
+        Logger.info("Memory usage:");
-        Log.info("Used: %d MB", used);
+        Logger.info("Used: %d MB", used);
-        Log.info("Total: %d MB", total);
+        Logger.info("Total: %d MB", total);
-        Log.info("Free: %d MB", free);
+        Logger.info("Free: %d MB", free);
-        Log.info("Max: %d MB", max);
+        Logger.info("Max: %d MB", max);
     }
 
     @Override

src/main/java/ua/nanit/limbo/server/commands/CmdVersion.java

@@ -1,14 +1,14 @@
 package ua.nanit.limbo.server.commands;
 
 import ua.nanit.limbo.server.Command;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 import ua.nanit.limbo.BuildConfig;
 
 public class CmdVersion implements Command {
 
     @Override
     public void execute() {
-        Log.info("Version: %s", BuildConfig.LIMBO_VERSION);
+        Logger.info("Version: %s", BuildConfig.LIMBO_VERSION);
     }
 
     @Override

src/main/java/ua/nanit/limbo/world/DimensionRegistry.java

@@ -21,7 +21,7 @@ import net.kyori.adventure.nbt.CompoundBinaryTag;
 import net.kyori.adventure.nbt.ListBinaryTag;
 import net.kyori.adventure.nbt.TagStringIO;
 import ua.nanit.limbo.server.LimboServer;
-import ua.nanit.limbo.server.Log;
+import ua.nanit.limbo.server.Logger;
 
 import java.io.*;
 import java.nio.charset.StandardCharsets;
@@ -33,8 +33,6 @@ public final class DimensionRegistry {
 
     private Dimension defaultDimension_1_16;
     private Dimension defaultDimension_1_18_2;
-    private Dimension dimension_1_20_5;
-    private Dimension dimension_1_21;
 
     private CompoundBinaryTag codec_1_16;
     private CompoundBinaryTag codec_1_18_2;
@@ -42,7 +40,6 @@ public final class DimensionRegistry {
     private CompoundBinaryTag codec_1_19_1;
     private CompoundBinaryTag codec_1_19_4;
     private CompoundBinaryTag codec_1_20;
-    private CompoundBinaryTag codec_1_21;
     private CompoundBinaryTag oldCodec;
 
     public DimensionRegistry(LimboServer server) {
@@ -73,10 +70,6 @@ public final class DimensionRegistry {
         return codec_1_20;
     }
 
-    public CompoundBinaryTag getCodec_1_21() {
-        return codec_1_21;
-    }
-
     public CompoundBinaryTag getOldCodec() {
         return oldCodec;
     }
@@ -89,30 +82,18 @@ public final class DimensionRegistry {
         return defaultDimension_1_18_2;
     }
 
-    public Dimension getDimension_1_20_5() {
-        return dimension_1_20_5;
-    }
-
-    public Dimension getDimension_1_21() {
-        return dimension_1_21;
-    }
-
     public void load(String def) throws IOException {
-        // On 1.16-1.16.1 different codec format
-        oldCodec = readCodecFile("/dimension/codec_old.snbt");
         codec_1_16 = readCodecFile("/dimension/codec_1_16.snbt");
         codec_1_18_2 = readCodecFile("/dimension/codec_1_18_2.snbt");
         codec_1_19 = readCodecFile("/dimension/codec_1_19.snbt");
         codec_1_19_1 = readCodecFile("/dimension/codec_1_19_1.snbt");
         codec_1_19_4 = readCodecFile("/dimension/codec_1_19_4.snbt");
         codec_1_20 = readCodecFile("/dimension/codec_1_20.snbt");
-        codec_1_21 = readCodecFile("/dimension/codec_1_21.snbt");
+        // On 1.16-1.16.1 different codec format
+        oldCodec = readCodecFile("/dimension/codec_old.snbt");
 
         defaultDimension_1_16 = getDefaultDimension(def, codec_1_16);
         defaultDimension_1_18_2 = getDefaultDimension(def, codec_1_18_2);
-
-        dimension_1_20_5 = getModernDimension(def, codec_1_20);
-        dimension_1_21 = getModernDimension(def, codec_1_21);
     }
 
     private Dimension getDefaultDimension(String def, CompoundBinaryTag tag) {
@@ -130,37 +111,29 @@ public final class DimensionRegistry {
             case "the_end":
                 return new Dimension(1, "minecraft:the_end", theEnd);
             default:
-                Log.warning("Undefined dimension type: '%s'. Using THE_END as default", def);
+                Logger.warning("Undefined dimension type: '%s'. Using THE_END as default", def);
                 return new Dimension(1, "minecraft:the_end", theEnd);
         }
     }
 
-    private Dimension getModernDimension(String def, CompoundBinaryTag tag) {
-        switch (def.toLowerCase()) {
-            case "overworld":
-                return new Dimension(0, "minecraft:overworld", tag);
-            case "the_nether":
-                return new Dimension(2, "minecraft:nether", tag);
-            case "the_end":
-                return new Dimension(3, "minecraft:the_end", tag);
-            default:
-                Log.warning("Undefined dimension type: '%s'. Using THE_END as default", def);
-                return new Dimension(3, "minecraft:the_end", tag);
-        }
-    }
-
     private CompoundBinaryTag readCodecFile(String resPath) throws IOException {
         InputStream in = server.getClass().getResourceAsStream(resPath);
 
-        if (in == null)
+        if(in == null)
             throw new FileNotFoundException("Cannot find dimension registry file");
 
         return TagStringIO.get().asCompound(streamToString(in));
     }
 
     private String streamToString(InputStream in) throws IOException {
-        try (BufferedReader bufReader = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8))) {
+        InputStreamReader isReader = new InputStreamReader(in, StandardCharsets.UTF_8);
-            return bufReader.lines().collect(Collectors.joining("\n"));
+        BufferedReader bufReader = new BufferedReader(isReader);
-        }
+        String content = bufReader.lines()
+                .collect(Collectors.joining("\n"));
+
+        isReader.close();
+        bufReader.close();
+
+        return content;
     }
 }

src/main/resources/logback.xml

@@ -1,30 +0,0 @@
-<?xml version="1.0" encoding="UTF-8" ?>
-<!DOCTYPE configuration>
-
-<configuration>
-    <import class="ch.qos.logback.classic.encoder.PatternLayoutEncoder"/>
-    <import class="ch.qos.logback.core.ConsoleAppender"/>
-    <import class="ch.qos.logback.core.FileAppender"/>
-
-    <timestamp key="bySecond" datePattern="yyyy-MM-dd"/>
-
-    <appender name="STDOUT" class="ConsoleAppender">
-        <encoder class="PatternLayoutEncoder">
-            <pattern>%d{HH:mm:ss.SSS} %-5level %logger{36} -%kvp- %msg%n</pattern>
-        </encoder>
-    </appender>
-
-    <appender name="FILE" class="FileAppender">
-        <file>logs/log-${bySecond}.txt</file>
-        <immediateFlush>true</immediateFlush>
-
-        <encoder class="PatternLayoutEncoder">
-            <pattern>%d{HH:mm:ss.SSS} %-5level %logger{36} -%kvp- %msg%n</pattern>
-        </encoder>
-    </appender>
-
-    <root level="info">
-        <appender-ref ref="FILE"/>
-        <appender-ref ref="STDOUT"/>
-    </root>
-</configuration>

src/main/resources/settings.yml

@@ -7,7 +7,7 @@ bind:
   ip: 'localhost'
   port: 65535
 
-# Max number of players can join to server
+# Max amount of players can join to server
 # Set -1 to make it infinite
 maxPlayers: 100
 
@@ -16,7 +16,7 @@ ping:
   description: '{"text": "&9NanoLimbo"}'
   version: 'NanoLimbo'
   # Return static protocol version number in ping result
-  # By default, its -1 to return the client version if it supported
+  # By default, its -1 to return the client version, if it supported
   # https://wiki.vg/Protocol_version_numbers
   protocol: -1
 
@@ -24,7 +24,7 @@ ping:
 dimension: THE_END
 
 # Whether to display the player in the player list
-# For 1.16.5 clients, the player list will be sent even if disabled, to avoid crash
+# For 1.16.5 clients, player list will be sent even if disabled, to avoid crash
 playerList:
   enable: false
   username: 'NanoLimbo'
@@ -50,12 +50,12 @@ brandName:
   enable: true
   content: 'NanoLimbo'
 
-# Message sends when player joins to the server
+# Message sends when player join to server
 joinMessage:
   enable: true
   text: '{"text": "&eWelcome to the Limbo!"}'
 
-# BossBar displays when player joins to the server
+# BossBar displays when player join to server
 # For 1.9+ clients
 bossBar:
   enable: true
@@ -87,7 +87,7 @@ title:
 #  - LEGACY
 #  - MODERN
 #  - BUNGEE_GUARD
-# Don't use secret if you do not use MODERN type
+# Don't use secret if you not use MODERN type
 infoForwarding:
   type: NONE
   secret: '<YOUR_SECRET_HERE>'
@@ -105,29 +105,27 @@ readTimeout: 30000
 # 3 - Display errors, warnings, info, debug
 debugLevel: 2
 
-# Warning! Do not touch params of this block if you are not completely sure what is this!
+# Warning! Do not touch params of this block, if you not completely sure what is this!
 netty:
-  # Use a Linux native transport type, if it possible
+  # Use Linux native transport type, if it possible
   useEpoll: true
   # EventLoopGroup threads count
   threads:
     bossGroup: 1
     workerGroup: 4
 
+# [Experimental]
 # Options to check incoming traffic and kick potentially malicious connections.
-# Take into account that player can send many small packets, for example, just moving mouse.
+# Take into account that player can send many small packets, for example just moving mouse.
 traffic:
-  # If true, then additional handler will be added to the channel pipeline
+  # If true, then additional handler will be added to channel pipeline
-  enable: true
+  enable: false
   # Max packet size in bytes
   # Unlimited if -1
-  maxPacketSize: 8192
+  packetSize: 1024
-  # The interval to measure packets over
+  # How many packets per second allowed for single connection
-  # Lowering this value will limit peak packets from players which would target people with bad connections
+  # Ignored if -1
-  # Raising this value will allow higher peak packet rates, which will help with people who have poor connections
+  packets: -1
-  # Ignored if -1.0
+  # How many bytes per second allowed for single connection
-  interval: 7.0
+  # Ignored if -1
-  # The maximum packets per second for players
+  bytes: 2048
-  # It is measured over the configured interval
-  # Ignored if -1.0
-  maxPacketRate: 500.0