Started refactoring session handlers

proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftConnection.java

@@ -69,7 +69,10 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
     @Override
     public void channelRead(ChannelHandlerContext ctx, Object msg) throws Exception {
         if (msg instanceof MinecraftPacket) {
-            sessionHandler.handle((MinecraftPacket) msg);
+            MinecraftPacket pkt = (MinecraftPacket) msg;
+            if (!pkt.handle(sessionHandler)) {
+                sessionHandler.handleGeneric((MinecraftPacket) msg);
+            }
         } else if (msg instanceof ByteBuf) {
             try {
                 sessionHandler.handleUnknown((ByteBuf) msg);

proxy/src/main/java/com/velocitypowered/proxy/connection/MinecraftSessionHandler.java

@@ -1,10 +1,11 @@
 package com.velocitypowered.proxy.connection;
 
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
+import com.velocitypowered.proxy.protocol.packet.*;
 import io.netty.buffer.ByteBuf;
 
 public interface MinecraftSessionHandler {
-    void handle(MinecraftPacket packet);
+    void handleGeneric(MinecraftPacket packet);
 
     default void handleUnknown(ByteBuf buf) {
         // No-op: we'll release the buffer later.
@@ -33,4 +34,30 @@ public interface MinecraftSessionHandler {
     default void writabilityChanged() {
 
     }
+
+    default boolean handle(BossBar packet) { return false; }
+    default boolean handle(Chat packet) { return false; }
+    default boolean handle(ClientSettings packet) { return false; }
+    default boolean handle(Disconnect packet) { return false; }
+    default boolean handle(EncryptionRequest packet) { return false; }
+    default boolean handle(EncryptionResponse packet) { return false; }
+    default boolean handle(Handshake packet) { return false; }
+    default boolean handle(HeaderAndFooter packet) { return false; }
+    default boolean handle(JoinGame packet) { return false; }
+    default boolean handle(KeepAlive packet) { return false; }
+    default boolean handle(LegacyHandshake packet) { return false; }
+    default boolean handle(LegacyPing packet) { return false; }
+    default boolean handle(LoginPluginMessage packet) { return false; }
+    default boolean handle(LoginPluginResponse packet) { return false; }
+    default boolean handle(PluginMessage packet) { return false; }
+    default boolean handle(Respawn packet) { return false; }
+    default boolean handle(ServerLogin packet) { return false; }
+    default boolean handle(ServerLoginSuccess packet) { return false; }
+    default boolean handle(SetCompression packet) { return false; }
+    default boolean handle(StatusPing packet) { return false; }
+    default boolean handle(StatusRequest packet) { return false; }
+    default boolean handle(StatusResponse packet) { return false; }
+    default boolean handle(TabCompleteRequest packet) { return false; }
+    default boolean handle(TabCompleteResponse packet) { return false; }
+    default boolean handle(TitlePacket packet) { return false; }
 }

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/BackendPlaySessionHandler.java

@@ -30,7 +30,7 @@ public class BackendPlaySessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         if (!serverConn.getPlayer().isActive()) {
             // Connection was left open accidentally. Close it so as to avoid "You logged in from another location"
             // errors.

proxy/src/main/java/com/velocitypowered/proxy/connection/backend/LoginSessionHandler.java

@@ -36,7 +36,7 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         if (packet instanceof EncryptionRequest) {
             throw new IllegalStateException("Backend server is online-mode!");
         } else if (packet instanceof LoginPluginMessage) {

proxy/src/main/java/com/velocitypowered/proxy/connection/client/ClientPlaySessionHandler.java

@@ -49,7 +49,7 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         VelocityServerConnection serverConnection = player.getConnectedServer();
         if (serverConnection == null) {
             // No server connection yet, probably transitioning.

proxy/src/main/java/com/velocitypowered/proxy/connection/client/HandshakeSessionHandler.java

@@ -35,74 +35,8 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
-        if (packet instanceof LegacyPing || packet instanceof LegacyHandshake) {
+    public boolean handle(LegacyPing packet) {
         connection.setProtocolVersion(ProtocolConstants.LEGACY);
-            handleLegacy(packet);
-            return;
-        }
-
-        if (!(packet instanceof Handshake)) {
-            throw new IllegalArgumentException("Did not expect packet " + packet.getClass().getName());
-        }
-
-        InitialInboundConnection ic = new InitialInboundConnection(connection, (Handshake) packet);
-
-        Handshake handshake = (Handshake) packet;
-        switch (handshake.getNextStatus()) {
-            case StateRegistry.STATUS_ID:
-                connection.setState(StateRegistry.STATUS);
-                connection.setProtocolVersion(handshake.getProtocolVersion());
-                connection.setSessionHandler(new StatusSessionHandler(server, connection, ic));
-                break;
-            case StateRegistry.LOGIN_ID:
-                connection.setState(StateRegistry.LOGIN);
-                connection.setProtocolVersion(handshake.getProtocolVersion());
-
-                if (!ProtocolConstants.isSupported(handshake.getProtocolVersion())) {
-                    connection.closeWith(Disconnect.create(TranslatableComponent.of("multiplayer.disconnect.outdated_client")));
-                    return;
-                }
-
-                InetAddress address = ((InetSocketAddress) connection.getChannel().remoteAddress()).getAddress();
-                if (!server.getIpAttemptLimiter().attempt(address)) {
-                    connection.closeWith(Disconnect.create(TextComponent.of("You are logging in too fast, try again later.")));
-                    return;
-                }
-
-                // Determine if we're using Forge (1.8 to 1.12, may not be the case in 1.13) and store that in the connection
-                boolean isForge = handshake.getServerAddress().endsWith("\0FML\0");
-                connection.setLegacyForge(isForge);
-
-                // Make sure legacy forwarding is not in use on this connection. Make sure that we do _not_ reject Forge
-                if (handshake.getServerAddress().contains("\0") && !isForge) {
-                    connection.closeWith(Disconnect.create(TextComponent.of("Running Velocity behind Velocity is unsupported.")));
-                    return;
-                }
-
-                // If the proxy is configured for modern forwarding, we must deny connections from 1.12.2 and lower,
-                // otherwise IP information will never get forwarded.
-                if (server.getConfiguration().getPlayerInfoForwardingMode() == PlayerInfoForwarding.MODERN && handshake.getProtocolVersion() <
-                        ProtocolConstants.MINECRAFT_1_13) {
-                    connection.closeWith(Disconnect.create(TextComponent.of("This server is only compatible with 1.13 and above.")));
-                    return;
-                }
-
-                server.getEventManager().fireAndForget(new ConnectionHandshakeEvent(ic));
-                connection.setSessionHandler(new LoginSessionHandler(server, connection, ic));
-                break;
-            default:
-                throw new IllegalArgumentException("Invalid state " + handshake.getNextStatus());
-        }
-    }
-
-    @Override
-    public void handleUnknown(ByteBuf buf) {
-        throw new IllegalStateException("Unknown data " + ByteBufUtil.hexDump(buf));
-    }
-
-    private void handleLegacy(MinecraftPacket packet) {
-        if (packet instanceof LegacyPing) {
         VelocityConfiguration configuration = server.getConfiguration();
         ServerPing ping = new ServerPing(
                 new ServerPing.Version(ProtocolConstants.MAXIMUM_GENERIC_VERSION, "Velocity " + ProtocolConstants.SUPPORTED_GENERIC_VERSION_STRING),
@@ -117,9 +51,73 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
                     // The disconnect packet is the same as the server response one.
                     connection.closeWith(LegacyDisconnect.fromPingResponse(LegacyPingResponse.from(event.getPing())));
                 }, connection.eventLoop());
-        } else if (packet instanceof LegacyHandshake) {
-            connection.closeWith(LegacyDisconnect.from(TextComponent.of("Your client is old, please upgrade!", TextColor.RED)));
+        return true;
     }
+
+    @Override
+    public boolean handle(LegacyHandshake packet) {
+        connection.closeWith(LegacyDisconnect.from(TextComponent.of("Your client is old, please upgrade!", TextColor.RED)));
+        return true;
+    }
+
+    @Override
+    public boolean handle(Handshake handshake) {
+        InitialInboundConnection ic = new InitialInboundConnection(connection, handshake);
+        switch (handshake.getNextStatus()) {
+            case StateRegistry.STATUS_ID:
+                connection.setState(StateRegistry.STATUS);
+                connection.setProtocolVersion(handshake.getProtocolVersion());
+                connection.setSessionHandler(new StatusSessionHandler(server, connection, ic));
+                return true;
+            case StateRegistry.LOGIN_ID:
+                connection.setState(StateRegistry.LOGIN);
+                connection.setProtocolVersion(handshake.getProtocolVersion());
+
+                if (!ProtocolConstants.isSupported(handshake.getProtocolVersion())) {
+                    connection.closeWith(Disconnect.create(TranslatableComponent.of("multiplayer.disconnect.outdated_client")));
+                    return true;
+                }
+
+                InetAddress address = ((InetSocketAddress) connection.getChannel().remoteAddress()).getAddress();
+                if (!server.getIpAttemptLimiter().attempt(address)) {
+                    connection.closeWith(Disconnect.create(TextComponent.of("You are logging in too fast, try again later.")));
+                    return true;
+                }
+
+                // Determine if we're using Forge (1.8 to 1.12, may not be the case in 1.13) and store that in the connection
+                boolean isForge = handshake.getServerAddress().endsWith("\0FML\0");
+                connection.setLegacyForge(isForge);
+
+                // Make sure legacy forwarding is not in use on this connection. Make sure that we do _not_ reject Forge
+                if (handshake.getServerAddress().contains("\0") && !isForge) {
+                    connection.closeWith(Disconnect.create(TextComponent.of("Running Velocity behind Velocity is unsupported.")));
+                    return true;
+                }
+
+                // If the proxy is configured for modern forwarding, we must deny connections from 1.12.2 and lower,
+                // otherwise IP information will never get forwarded.
+                if (server.getConfiguration().getPlayerInfoForwardingMode() == PlayerInfoForwarding.MODERN && handshake.getProtocolVersion() <
+                        ProtocolConstants.MINECRAFT_1_13) {
+                    connection.closeWith(Disconnect.create(TextComponent.of("This server is only compatible with 1.13 and above.")));
+                    return true;
+                }
+
+                server.getEventManager().fireAndForget(new ConnectionHandshakeEvent(ic));
+                connection.setSessionHandler(new LoginSessionHandler(server, connection, ic));
+                return true;
+            default:
+                throw new IllegalArgumentException("Invalid state " + handshake.getNextStatus());
+        }
+    }
+
+    @Override
+    public void handleGeneric(MinecraftPacket packet) {
+
+    }
+
+    @Override
+    public void handleUnknown(ByteBuf buf) {
+        throw new IllegalStateException("Unknown data " + ByteBufUtil.hexDump(buf));
     }
 
     private static class LegacyInboundConnection implements InboundConnection {

proxy/src/main/java/com/velocitypowered/proxy/connection/client/InitialConnectSessionHandler.java

@@ -11,7 +11,7 @@ public class InitialConnectSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         // No-op: will never handle packets
     }
 

proxy/src/main/java/com/velocitypowered/proxy/connection/client/LoginSessionHandler.java

@@ -59,7 +59,7 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         if (packet instanceof LoginPluginResponse) {
             LoginPluginResponse lpr = (LoginPluginResponse) packet;
             if (lpr.getId() == playerInfoId) {

proxy/src/main/java/com/velocitypowered/proxy/connection/client/StatusSessionHandler.java

@@ -29,7 +29,7 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         Preconditions.checkArgument(packet instanceof StatusPing || packet instanceof StatusRequest,
                 "Unrecognized packet type " + packet.getClass().getName());
 

proxy/src/main/java/com/velocitypowered/proxy/protocol/MinecraftPacket.java

@@ -1,9 +1,12 @@
 package com.velocitypowered.proxy.protocol;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import io.netty.buffer.ByteBuf;
 
 public interface MinecraftPacket {
     void decode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion);
 
     void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion);
+
+    boolean handle(MinecraftSessionHandler handler);
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/BossBar.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -150,4 +151,9 @@ public class BossBar implements MinecraftPacket {
                 break;
         }
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Chat.java

@@ -1,6 +1,7 @@
 package com.velocitypowered.proxy.protocol.packet;
 
 import com.google.common.base.Preconditions;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -63,6 +64,11 @@ public class Chat implements MinecraftPacket {
         }
     }
 
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
+
     public static Chat createClientbound(Component component) {
         return createClientbound(component, CHAT);
     }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ClientSettings.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -111,4 +112,9 @@ public class ClientSettings implements MinecraftPacket {
             ProtocolUtils.writeVarInt(buf, mainHand);
         }
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Disconnect.java

@@ -1,6 +1,7 @@
 package com.velocitypowered.proxy.protocol.packet;
 
 import com.google.common.base.Preconditions;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -43,6 +44,11 @@ public class Disconnect implements MinecraftPacket {
         ProtocolUtils.writeString(buf, reason);
     }
 
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
+
     public static Disconnect create(Component component) {
         Preconditions.checkNotNull(component, "component");
         return new Disconnect(ComponentSerializers.JSON.serialize(component));

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/EncryptionRequest.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -48,4 +49,9 @@ public class EncryptionRequest implements MinecraftPacket {
         ProtocolUtils.writeByteArray(buf, publicKey);
         ProtocolUtils.writeByteArray(buf, verifyToken);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/EncryptionResponse.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -46,4 +47,9 @@ public class EncryptionResponse implements MinecraftPacket {
         ProtocolUtils.writeByteArray(buf, sharedSecret);
         ProtocolUtils.writeByteArray(buf, verifyToken);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Handshake.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -68,4 +69,9 @@ public class Handshake implements MinecraftPacket {
         buf.writeShort(this.port);
         ProtocolUtils.writeVarInt(buf, this.nextStatus);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/HeaderAndFooter.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants.Direction;
 import io.netty.buffer.ByteBuf;
@@ -51,6 +52,11 @@ public class HeaderAndFooter implements MinecraftPacket {
         writeString(buf, footer);
     }
 
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
+
     public static HeaderAndFooter create(Component header, Component footer) {
         ComponentSerializer<Component, Component, String> json = ComponentSerializers.JSON;
         return new HeaderAndFooter(json.serialize(header), json.serialize(footer));

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/JoinGame.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -112,4 +113,9 @@ public class JoinGame implements MinecraftPacket {
         ProtocolUtils.writeString(buf, levelType);
         buf.writeBoolean(reducedDebugInfo);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/KeepAlive.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -42,4 +43,9 @@ public class KeepAlive implements MinecraftPacket {
             ProtocolUtils.writeVarInt(buf, (int) randomId);
         }
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LegacyHandshake.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import io.netty.buffer.ByteBuf;
@@ -14,4 +15,9 @@ public class LegacyHandshake implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         throw new UnsupportedOperationException();
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LegacyPing.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import io.netty.buffer.ByteBuf;
@@ -14,4 +15,9 @@ public class LegacyPing implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         throw new UnsupportedOperationException();
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LoginPluginMessage.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -61,4 +62,9 @@ public class LoginPluginMessage implements MinecraftPacket {
         ProtocolUtils.writeString(buf, channel);
         buf.writeBytes(data);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/LoginPluginResponse.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -61,4 +62,9 @@ public class LoginPluginResponse implements MinecraftPacket {
         buf.writeBoolean(success);
         buf.writeBytes(data);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/PluginMessage.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -46,4 +47,9 @@ public class PluginMessage implements MinecraftPacket {
         ProtocolUtils.writeString(buf, channel);
         buf.writeBytes(data);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/Respawn.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -78,4 +79,9 @@ public class Respawn implements MinecraftPacket {
         buf.writeByte(gamemode);
         ProtocolUtils.writeString(buf, levelType);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerLogin.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -32,4 +33,9 @@ public class ServerLogin implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         ProtocolUtils.writeString(buf, username);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/ServerLoginSuccess.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -46,4 +47,9 @@ public class ServerLoginSuccess implements MinecraftPacket {
         ProtocolUtils.writeString(buf, uuid.toString());
         ProtocolUtils.writeString(buf, username);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/SetCompression.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -38,4 +39,9 @@ public class SetCompression implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         ProtocolUtils.writeVarInt(buf, threshold);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/StatusPing.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import io.netty.buffer.ByteBuf;
@@ -16,4 +17,9 @@ public class StatusPing implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         buf.writeLong(randomId);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/StatusRequest.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import io.netty.buffer.ByteBuf;
@@ -25,4 +26,9 @@ public class StatusRequest implements MinecraftPacket {
     public String toString() {
         return "StatusRequest";
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/StatusResponse.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -32,4 +33,9 @@ public class StatusResponse implements MinecraftPacket {
     public void encode(ByteBuf buf, ProtocolConstants.Direction direction, int protocolVersion) {
         ProtocolUtils.writeString(buf, status);
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/TabCompleteRequest.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -79,4 +80,9 @@ public class TabCompleteRequest implements MinecraftPacket {
             buf.writeLong(position);
         }
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/TabCompleteResponse.java

@@ -1,5 +1,6 @@
 package com.velocitypowered.proxy.protocol.packet;
 
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -37,4 +38,9 @@ public class TabCompleteResponse implements MinecraftPacket {
             ProtocolUtils.writeString(buf, offer);
         }
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/protocol/packet/TitlePacket.java

@@ -1,6 +1,7 @@
 package com.velocitypowered.proxy.protocol.packet;
 
 import com.google.common.base.Preconditions;
+import com.velocitypowered.proxy.connection.MinecraftSessionHandler;
 import com.velocitypowered.proxy.protocol.MinecraftPacket;
 import com.velocitypowered.proxy.protocol.ProtocolConstants;
 import com.velocitypowered.proxy.protocol.ProtocolUtils;
@@ -134,4 +135,9 @@ public class TitlePacket implements MinecraftPacket {
                 ", fadeOut=" + fadeOut +
                 '}';
     }
+
+    @Override
+    public boolean handle(MinecraftSessionHandler handler) {
+        return handler.handle(this);
+    }
 }

proxy/src/main/java/com/velocitypowered/proxy/server/ping/PingSessionHandler.java

@@ -42,7 +42,7 @@ public class PingSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public void handle(MinecraftPacket packet) {
+    public void handleGeneric(MinecraftPacket packet) {
         Preconditions.checkState(packet instanceof StatusResponse, "Did not get status response back from connection");
 
         // All good!