chore: move packets to interfaces

api/src/main/java/net/hypejet/jet/player/PlayerConnection.java

@@ -2,7 +2,7 @@
 
 import net.hypejet.jet.protocol.ProtocolState;
 import net.hypejet.jet.protocol.packet.clientbound.ClientBoundPacket;
-import net.hypejet.jet.protocol.packet.clientbound.login.DisconnectPacket;
+import net.hypejet.jet.protocol.packet.clientbound.login.disconnect.DisconnectPacket;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.NonNull;
 

api/src/main/java/net/hypejet/jet/protocol/packet/clientbound/ClientBoundPacket.java

@@ -9,48 +9,28 @@
  * @since 1.0
  * @author Codestech
  */
-public abstract class ClientBoundPacket {
-
-    private final int packetId;
-    private final ProtocolState protocolState;
-
-    /**
-     * Constructs a {@link ClientBoundPacket client-bound packet}.
-     *
-     * @param packetId an id of the packet
-     * @param protocolState a protocol state of the packet
-     * @since 1.0
-     */
-    public ClientBoundPacket(int packetId, @NonNull ProtocolState protocolState) {
-        this.packetId = packetId;
-        this.protocolState = protocolState;
-    }
-
+public interface ClientBoundPacket {
     /**
      * Gets an identifier of the packet.
      *
      * @return the identifier.
      * @since 1.0
      */
-    public final int getPacketId() {
-        return this.packetId;
-    }
+    int getPacketId();
 
     /**
      * Gets a {@link ProtocolState protocol state} of the packet.
      *
      * @return the protocol state.
      * @since 1.0
      */
-    public final @NonNull ProtocolState getProtocolState() {
-        return this.protocolState;
-    }
+    @NonNull ProtocolState getProtocolState();
 
     /**
      * Writes the packet to a {@link NetworkBuffer network buffer}.
      *
      * @param buffer the byte buffer
      * @since 1.0
      */
-    public abstract void write(@NonNull NetworkBuffer buffer);
+    void write(@NonNull NetworkBuffer buffer);
 }

api/src/main/java/net/hypejet/jet/protocol/packet/clientbound/login/disconnect/DisconnectPacket.java

@@ -0,0 +1,56 @@
+package net.hypejet.jet.protocol.packet.clientbound.login.disconnect;
+
+import net.hypejet.jet.protocol.packet.clientbound.ClientBoundPacket;
+import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * Represents a {@link ClientBoundPacket client-bound packet} sent by a server to disconnect a player.
+ *
+ * @since 1.0
+ * @author Codestech
+ */
+public sealed interface DisconnectPacket extends ClientBoundPacket permits DisconnectPacketImpl {
+    /**
+     * Gets a reason of the disconnection.
+     *
+     * @return the reason
+     * @since 1.0
+     */
+    @NonNull Component reason();
+
+    /**
+     * Creates a new {@link Builder disconnect packet builder}.
+     *
+     * @return the builder
+     * @since 1.0
+     */
+    static @NonNull Builder builder() {
+        return new DisconnectPacketImpl.Builder();
+    }
+
+    /**
+     * Represents a builder that creates a {@link DisconnectPacket disconnect packet}.
+     *
+     * @since 1.0
+     * @author Codestech
+     */
+    interface Builder {
+        /**
+         * Sets a reason of the disconnection.
+         *
+         * @param reason the reason
+         * @return the builder
+         * @since 1.0
+         */
+        @NonNull Builder reason(@NonNull Component reason);
+
+        /**
+         * Builds the {@link DisconnectPacket disconnect packet}.
+         *
+         * @return the disconnect packet
+         * @since 1.0
+         */
+        @NonNull DisconnectPacket build();
+    }
+}

api/src/main/java/net/hypejet/jet/protocol/packet/clientbound/login/disconnect/DisconnectPacketImpl.java

@@ -0,0 +1,55 @@
+package net.hypejet.jet.protocol.packet.clientbound.login.disconnect;
+
+import net.hypejet.jet.buffer.NetworkBuffer;
+import net.hypejet.jet.protocol.ProtocolState;
+import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.NonNull;
+
+/**
+ * Represents an implementation of {@link DisconnectPacket disconnect packet}.
+ *
+ * @param reason a reason of the disconnection
+ * @since 1.0
+ * @author Codestech
+ * @see DisconnectPacket
+ */
+record DisconnectPacketImpl(@NonNull Component reason) implements DisconnectPacket {
+
+    @Override
+    public void write(@NonNull NetworkBuffer buffer) {
+        buffer.writeJsonTextComponent(this.reason);
+    }
+
+    @Override
+    public int getPacketId() {
+        return 0;
+    }
+
+    @Override
+    public @NonNull ProtocolState getProtocolState() {
+        return ProtocolState.LOGIN;
+    }
+
+    /**
+     * Represents an implementation of {@link DisconnectPacket.Builder disconnect packet builder}.
+     *
+     * @since 1.0
+     * @author Codestech
+     * @see DisconnectPacket.Builder
+     */
+    static final class Builder implements DisconnectPacket.Builder {
+
+        private Component reason = Component.empty();
+
+        @Override
+        public DisconnectPacket.@NonNull Builder reason(@NonNull Component reason) {
+            this.reason = reason;
+            return this;
+        }
+
+        @Override
+        public @NonNull DisconnectPacket build() {
+            return new DisconnectPacketImpl(this.reason);
+        }
+    }
+}

api/src/main/java/net/hypejet/jet/protocol/packet/serverbound/handshake/HandshakePacket.java

@@ -1,18 +1,47 @@
 package net.hypejet.jet.protocol.packet.serverbound.handshake;
 
+import net.hypejet.jet.player.PlayerConnection;
 import net.hypejet.jet.protocol.ProtocolState;
 import net.hypejet.jet.protocol.packet.serverbound.ServerBoundPacket;
 import org.checkerframework.checker.nullness.qual.NonNull;
 
 /**
  * Represents a {@link ServerBoundPacket server-bound packet} that initializes connection of a player.
  *
- * @param protocolVersion a version of the Minecraft protocol
- * @param serverAddress an address of the server
- * @param serverPort a port of the server
- * @param nextState a next protocol state, which the connection will switch to
  * @since 1.0
  * @author Codestech
  */
-public record HandshakePacket(int protocolVersion, @NonNull String serverAddress,
-                              int serverPort, @NonNull ProtocolState nextState) implements ServerBoundPacket {}
+public interface HandshakePacket extends ServerBoundPacket {
+    /**
+     * Gets a version of the Minecraft protocol.
+     *
+     * @return the version
+     * @since 1.0
+     */
+    int protocolVersion();
+
+    /**
+     * Gets an address of a server that the client tries to connect to.
+     *
+     * @return the address
+     * @since 1.0
+     */
+    @NonNull String serverAddress();
+
+    /**
+     * Gets a port of a server that the client tries to connect to.
+     *
+     * @return the port
+     * @since 1.0
+     */
+    int serverPort();
+
+    /**
+     * Gets a next {@link ProtocolState protocol state}, which a {@link PlayerConnection player connection} will switch
+     * to.
+     *
+     * @return the protocol state
+     * @since 1.0
+     */
+    @NonNull ProtocolState nextState();
+}

api/src/main/java/net/hypejet/jet/protocol/packet/serverbound/login/LoginRequestPacket.java

@@ -8,10 +8,23 @@
 /**
  * Represents a {@link ServerBoundPacket server-bound packet} that requests a server to send a login data.
  *
- * @param username a username of a player that sends the packet
- * @param uniqueId a unique id of a player that sends the packet
  * @since 1.0
  * @author Codestech
  */
-public record LoginRequestPacket(@NonNull String username, @NonNull UUID uniqueId)
-        implements ServerBoundPacket {}
+public interface LoginRequestPacket extends ServerBoundPacket {
+    /**
+     * Gets a username of a player that sends the packet.
+     *
+     * @return the username
+     * @since 1.0
+     */
+    @NonNull String username();
+
+    /**
+     * Gets a {@link UUID unique identifier} of a player that sends the packet.
+     *
+     * @return the unique identifier
+     * @since 1.0
+     */
+    @NonNull UUID uniqueId();
+}

server/src/main/java/net/hypejet/jet/server/Main.java

@@ -6,7 +6,7 @@
 import io.netty.channel.nio.NioEventLoopGroup;
 import io.netty.channel.socket.nio.NioServerSocketChannel;
 import net.hypejet.jet.server.network.PlayerChannelInitializer;
-import net.hypejet.jet.server.protocol.JetServerBoundPacketRegistry;
+import net.hypejet.jet.server.protocol.ServerBoundPacketRegistry;
 
 public class Main {
     public static void main(String[] args) {
@@ -17,7 +17,7 @@ public static void main(String[] args) {
             ServerBootstrap bootstrap = new ServerBootstrap()
                     .group(bossGroup, workerGroup)
                     .channel(NioServerSocketChannel.class)
-                    .childHandler(new PlayerChannelInitializer(new JetServerBoundPacketRegistry()));
+                    .childHandler(new PlayerChannelInitializer(new ServerBoundPacketRegistry()));
 
             ChannelFuture future = bootstrap.bind(25565).sync();
             future.channel().closeFuture().sync();

server/src/main/java/net/hypejet/jet/server/network/PlayerChannelInitializer.java

@@ -2,11 +2,11 @@
 
 import io.netty.channel.ChannelInitializer;
 import io.netty.channel.socket.SocketChannel;
-import net.hypejet.jet.protocol.packet.serverbound.ServerBoundPacketRegistry;
 import net.hypejet.jet.server.network.serialization.PacketDecoder;
 import net.hypejet.jet.server.network.serialization.PacketEncoder;
 import net.hypejet.jet.server.network.serialization.PacketLengthEncoder;
 import net.hypejet.jet.server.player.JetPlayerConnection;
+import net.hypejet.jet.server.protocol.ServerBoundPacketRegistry;
 import org.checkerframework.checker.nullness.qual.NonNull;
 
 public final class PlayerChannelInitializer extends ChannelInitializer<SocketChannel> {

server/src/main/java/net/hypejet/jet/server/network/serialization/PacketDecoder.java

@@ -6,9 +6,9 @@
 import net.hypejet.jet.buffer.ReadOnlyNetworkBuffer;
 import net.hypejet.jet.protocol.ProtocolState;
 import net.hypejet.jet.protocol.packet.serverbound.ServerBoundPacket;
-import net.hypejet.jet.protocol.packet.serverbound.ServerBoundPacketRegistry;
 import net.hypejet.jet.server.buffer.ReadOnlyNetworkBufferImpl;
 import net.hypejet.jet.server.player.JetPlayerConnection;
+import net.hypejet.jet.server.protocol.ServerBoundPacketRegistry;
 import org.checkerframework.checker.nullness.qual.NonNull;
 
 import java.util.List;