Fix issue produced by velocity 216

Author: Exceptionflug

pom.xml

@@ -21,7 +21,7 @@
 
         <build.number>unknown</build.number>
         <bungeecord.version>1.17-R0.1-SNAPSHOT</bungeecord.version>
-        <velocity.version>3.0.0</velocity.version>
+        <velocity.version>3.1.0</velocity.version>
         <bytebuddy.version>1.11.13</bytebuddy.version>
         <data.version>2.2.4</data.version>
     </properties>

protocolize-velocity/src/main/java/dev/simplix/protocolize/velocity/providers/VelocityProtocolRegistrationProvider.java

@@ -44,6 +44,8 @@ public final class VelocityProtocolRegistrationProvider implements ProtocolRegis
     private Constructor<StateRegistry.PacketMapping> packetMappingConstructor;
     private Field versionsField;
     private Field packetClassToIdField;
+    private Field serverboundField;
+    private Field clientboundField;
     private Method registerMethod;
 
     {
@@ -56,6 +58,10 @@ public final class VelocityProtocolRegistrationProvider implements ProtocolRegis
             versionsField.setAccessible(true);
             packetClassToIdField = StateRegistry.PacketRegistry.ProtocolRegistry.class.getDeclaredField("packetClassToId");
             packetClassToIdField.setAccessible(true);
+            clientboundField = StateRegistry.class.getDeclaredField("clientbound");
+            clientboundField.setAccessible(true);
+            serverboundField = StateRegistry.class.getDeclaredField("serverbound");
+            serverboundField.setAccessible(true);
         } catch (Exception exception) {
             log.error("Exception occurred while initializing VelocityProtocolRegistrationProvider:", exception);
         }
@@ -77,7 +83,9 @@ public void registerPacket(List<ProtocolIdMapping> mappings, Protocol protocol,
             if (stateRegistry == null) {
                 return;
             }
-            StateRegistry.PacketRegistry registry = direction == PacketDirection.SERVERBOUND ? stateRegistry.serverbound : stateRegistry.clientbound;
+            StateRegistry.PacketRegistry registry = direction == PacketDirection.SERVERBOUND ?
+                (StateRegistry.PacketRegistry) serverboundField.get(stateRegistry) :
+                (StateRegistry.PacketRegistry) clientboundField.get(stateRegistry);
             Class<? extends MinecraftPacket> velocityPacket = generateVelocityPacket(packetClass);
             List<StateRegistry.PacketMapping> velocityMappings = new ArrayList<>();