Remove essentially all use of Java Optionals from the API

Also fix extended handshake event handling

api/src/main/java/com/velocitypowered/api/event/ResultedEvent.java

@@ -9,7 +9,6 @@ package com.velocitypowered.api.event;
 
 import com.google.common.base.Preconditions;
 import java.util.Objects;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.plain.PlainComponentSerializer;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -85,34 +84,30 @@ public interface ResultedEvent<R extends ResultedEvent.Result> {
    */
   final class ComponentResult implements Result {
 
-    private static final ComponentResult ALLOWED = new ComponentResult(true, null);
+    private static final ComponentResult ALLOWED = new ComponentResult(null);
 
-    private final boolean status;
     private final @Nullable Component reason;
 
-    protected ComponentResult(boolean status, @Nullable Component reason) {
-      this.status = status;
+    protected ComponentResult(@Nullable Component reason) {
       this.reason = reason;
     }
 
     @Override
     public boolean isAllowed() {
-      return status;
+      return reason == null;
     }
 
-    public Optional<Component> reason() {
-      return Optional.ofNullable(reason);
+    public @Nullable Component reason() {
+      return reason;
     }
 
     @Override
     public String toString() {
-      if (status) {
+      if (reason == null) {
         return "allowed";
-      }
-      if (reason != null) {
+      } else {
         return "denied: " + PlainComponentSerializer.plain().serialize(reason);
       }
-      return "denied";
     }
 
     public static ComponentResult allowed() {
@@ -121,7 +116,7 @@ public interface ResultedEvent<R extends ResultedEvent.Result> {
 
     public static ComponentResult denied(Component reason) {
       Preconditions.checkNotNull(reason, "reason");
-      return new ComponentResult(false, reason);
+      return new ComponentResult(reason);
     }
 
     @Override
@@ -133,12 +128,12 @@ public interface ResultedEvent<R extends ResultedEvent.Result> {
         return false;
       }
       ComponentResult that = (ComponentResult) o;
-      return status == that.status && Objects.equals(reason, that.reason);
+      return Objects.equals(reason, that.reason);
     }
 
     @Override
     public int hashCode() {
-      return Objects.hash(status, reason);
+      return Objects.hash(reason);
     }
   }
 }

api/src/main/java/com/velocitypowered/api/event/command/CommandExecuteEvent.java

@@ -12,7 +12,6 @@ import com.velocitypowered.api.command.CommandSource;
 import com.velocitypowered.api.event.ResultedEvent;
 import com.velocitypowered.api.event.command.CommandExecuteEvent.CommandResult;
 import java.util.Objects;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -45,8 +44,8 @@ public interface CommandExecuteEvent extends ResultedEvent<CommandResult> {
       this.command = command;
     }
 
-    public Optional<String> modifiedCommand() {
-      return Optional.ofNullable(command);
+    public @Nullable String modifiedCommand() {
+      return command;
     }
 
     public boolean isForwardToServer() {

api/src/main/java/com/velocitypowered/api/event/player/GameProfileRequestEventImpl.java

@@ -34,7 +34,7 @@ public final class GameProfileRequestEventImpl implements GameProfileRequestEven
       boolean onlineMode) {
     this.connection = Preconditions.checkNotNull(connection, "connection");
     this.originalProfile = Preconditions.checkNotNull(originalProfile, "originalProfile");
-    this.username = originalProfile.getName();
+    this.username = originalProfile.name();
     this.onlineMode = onlineMode;
   }
 

api/src/main/java/com/velocitypowered/api/event/player/KickedFromServerEvent.java

@@ -12,7 +12,6 @@ import com.velocitypowered.api.event.ResultedEvent;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 import java.util.Objects;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -34,7 +33,7 @@ public interface KickedFromServerEvent extends
    *
    * @return the server kicked the player from the server
    */
-  Optional<Component> serverKickReason();
+  @Nullable Component serverKickReason();
 
   /**
    * Returns whether or not the player got kicked while connecting to another server.

api/src/main/java/com/velocitypowered/api/event/player/KickedFromServerEventImpl.java

@@ -10,7 +10,6 @@ package com.velocitypowered.api.event.player;
 import com.google.common.base.Preconditions;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.NonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -72,8 +71,8 @@ public final class KickedFromServerEventImpl implements KickedFromServerEvent {
    * @return the server kicked the player from the server
    */
   @Override
-  public Optional<Component> serverKickReason() {
-    return Optional.ofNullable(originalReason);
+  public @Nullable Component serverKickReason() {
+    return originalReason;
   }
 
   /**

api/src/main/java/com/velocitypowered/api/event/player/PlayerChooseInitialServerEvent.java

@@ -9,7 +9,7 @@ package com.velocitypowered.api.event.player;
 
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Fired when a player has finished connecting to the proxy and we need to choose the first server
@@ -19,7 +19,7 @@ public interface PlayerChooseInitialServerEvent {
 
   Player player();
 
-  Optional<RegisteredServer> initialServer();
+  @Nullable RegisteredServer initialServer();
 
   /**
    * Sets the new initial server.

api/src/main/java/com/velocitypowered/api/event/player/PlayerChooseInitialServerEventImpl.java

@@ -10,7 +10,6 @@ package com.velocitypowered.api.event.player;
 import com.google.common.base.Preconditions;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
@@ -38,8 +37,8 @@ public class PlayerChooseInitialServerEventImpl implements PlayerChooseInitialSe
   }
 
   @Override
-  public Optional<RegisteredServer> initialServer() {
-    return Optional.ofNullable(initialServer);
+  public @Nullable RegisteredServer initialServer() {
+    return initialServer;
   }
 
   /**
@@ -47,7 +46,7 @@ public class PlayerChooseInitialServerEventImpl implements PlayerChooseInitialSe
    * @param server the initial server the player should connect to
    */
   @Override
-  public void setInitialServer(RegisteredServer server) {
+  public void setInitialServer(@Nullable RegisteredServer server) {
     this.initialServer = server;
   }
 

api/src/main/java/com/velocitypowered/api/event/player/ServerConnectedEvent.java

@@ -9,7 +9,7 @@ package com.velocitypowered.api.event.player;
 
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * This event is fired once the player has successfully connected to the target server and the
@@ -21,5 +21,5 @@ public interface ServerConnectedEvent {
 
   RegisteredServer target();
 
-  Optional<RegisteredServer> previousServer();
+  @Nullable RegisteredServer previousServer();
 }

api/src/main/java/com/velocitypowered/api/event/player/ServerConnectedEventImpl.java

@@ -10,7 +10,6 @@ package com.velocitypowered.api.event.player;
 import com.google.common.base.Preconditions;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
@@ -47,8 +46,8 @@ public final class ServerConnectedEventImpl implements ServerConnectedEvent {
   }
 
   @Override
-  public Optional<RegisteredServer> previousServer() {
-    return Optional.ofNullable(previousServer);
+  public @Nullable RegisteredServer previousServer() {
+    return previousServer;
   }
 
   @Override

api/src/main/java/com/velocitypowered/api/event/player/ServerPreConnectEvent.java

@@ -14,7 +14,6 @@ import com.velocitypowered.api.proxy.player.ConnectionRequestBuilder;
 import com.velocitypowered.api.proxy.player.ConnectionRequestBuilder.Status;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 import java.util.Objects;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
@@ -60,8 +59,8 @@ public interface ServerPreConnectEvent extends ResultedEvent<ServerPreConnectEve
       return target != null;
     }
 
-    public Optional<RegisteredServer> target() {
-      return Optional.ofNullable(target);
+    public @Nullable RegisteredServer target() {
+      return target;
     }
 
     @Override

api/src/main/java/com/velocitypowered/api/plugin/PluginDescription.java

@@ -13,8 +13,8 @@ import com.velocitypowered.api.plugin.meta.PluginDependency;
 import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
-import java.util.Optional;
 import java.util.regex.Pattern;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Represents metadata for a specific version of a plugin.
@@ -39,41 +39,41 @@ public interface PluginDescription {
   /**
    * Gets the name of the {@link Plugin} within this container.
    *
-   * @return an {@link Optional} with the plugin name, may be empty
+   * @return a String with the plugin name or the plugin ID
    * @see Plugin#name()
    */
-  default Optional<String> name() {
-    return Optional.empty();
+  default String name() {
+    return id();
   }
 
   /**
    * Gets the version of the {@link Plugin} within this container.
    *
-   * @return an {@link Optional} with the plugin version, may be empty
+   * @return a String with the plugin version, may be null
    * @see Plugin#version()
    */
-  default Optional<String> version() {
-    return Optional.empty();
+  default @Nullable String version() {
+    return null;
   }
 
   /**
    * Gets the description of the {@link Plugin} within this container.
    *
-   * @return an {@link Optional} with the plugin description, may be empty
+   * @return a String with the plugin description, may be null
    * @see Plugin#description()
    */
-  default Optional<String> description() {
-    return Optional.empty();
+  default @Nullable String description() {
+    return null;
   }
 
   /**
    * Gets the url or website of the {@link Plugin} within this container.
    *
-   * @return an {@link Optional} with the plugin url, may be empty
+   * @return an String with the plugin url, may be null
    * @see Plugin#url()
    */
-  default Optional<String> url() {
-    return Optional.empty();
+  default @Nullable String url() {
+    return null;
   }
 
   /**
@@ -96,16 +96,16 @@ public interface PluginDescription {
     return ImmutableSet.of();
   }
 
-  default Optional<PluginDependency> getDependency(String id) {
-    return Optional.empty();
+  default @Nullable PluginDependency getDependency(String id) {
+    return null;
   }
 
   /**
    * Returns the file path the plugin was loaded from.
    *
-   * @return the path the plugin was loaded from or {@link Optional#empty()} if unknown
+   * @return the path the plugin was loaded from or {@code null} if unknown
    */
-  default Optional<Path> file() {
-    return Optional.empty();
+  default @Nullable Path file() {
+    return null;
   }
 }

api/src/main/java/com/velocitypowered/api/plugin/PluginManager.java

@@ -7,9 +7,11 @@
 
 package com.velocitypowered.api.plugin;
 
+import static java.util.Objects.requireNonNull;
+
 import java.nio.file.Path;
 import java.util.Collection;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Manages plugins loaded on the proxy. This manager can retrieve {@link PluginContainer}s from
@@ -24,7 +26,7 @@ public interface PluginManager {
    * @param instance the instance
    * @return the container
    */
-  Optional<PluginContainer> fromInstance(Object instance);
+  @Nullable PluginContainer fromInstance(Object instance);
 
   /**
    * Retrieves a {@link PluginContainer} based on its ID.
@@ -32,7 +34,7 @@ public interface PluginManager {
    * @param id the plugin ID
    * @return the plugin, if available
    */
-  Optional<PluginContainer> getPlugin(String id);
+  @Nullable PluginContainer getPlugin(String id);
 
   /**
    * Gets a {@link Collection} of all {@link PluginContainer}s.
@@ -57,4 +59,13 @@ public interface PluginManager {
    * @throws UnsupportedOperationException if the operation is not applicable to this plugin
    */
   void addToClasspath(Object plugin, Path path);
+
+  default PluginContainer ensurePluginContainer(Object plugin) {
+    requireNonNull(plugin, "plugin");
+    PluginContainer container = fromInstance(plugin);
+    if (container == null) {
+      throw new IllegalArgumentException("Specified plugin is not loaded");
+    }
+    return container;
+  }
 }

api/src/main/java/com/velocitypowered/api/plugin/meta/PluginDependency.java

@@ -12,7 +12,6 @@ import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Strings.emptyToNull;
 
 import java.util.Objects;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
@@ -43,17 +42,17 @@ public final class PluginDependency {
    *
    * @return the plugin ID
    */
-  public String getId() {
+  public String id() {
     return id;
   }
 
   /**
    * Returns the version this {@link PluginDependency} should match.
    *
-   * @return an {@link Optional} with the plugin version, may be empty
+   * @return a String with the plugin version, may be {@code null}
    */
-  public Optional<String> getVersion() {
-    return Optional.ofNullable(version);
+  public @Nullable String version() {
+    return version;
   }
 
   /**
@@ -61,7 +60,7 @@ public final class PluginDependency {
    *
    * @return true if dependency is optional
    */
-  public boolean isOptional() {
+  public boolean optional() {
     return optional;
   }
 

api/src/main/java/com/velocitypowered/api/proxy/ProxyServer.java

@@ -19,12 +19,11 @@ import com.velocitypowered.api.proxy.server.RegisteredServer;
 import com.velocitypowered.api.proxy.server.ServerInfo;
 import com.velocitypowered.api.scheduler.Scheduler;
 import com.velocitypowered.api.util.ProxyVersion;
-import java.net.SocketAddress;
 import java.util.Collection;
-import java.util.Optional;
 import java.util.UUID;
 import net.kyori.adventure.audience.Audience;
 import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Provides an interface to a Minecraft server proxy.
@@ -48,17 +47,17 @@ public interface ProxyServer extends Audience {
    * is case-insensitive.
    *
    * @param username the username to search for
-   * @return an {@link Optional} with the player, which may be empty
+   * @return the player instance, if connected, else {@code null}
    */
-  Optional<Player> getPlayer(String username);
+  @Nullable Player player(String username);
 
   /**
    * Retrieves the player currently connected to this proxy by their Minecraft UUID.
    *
    * @param uuid the UUID
-   * @return an {@link Optional} with the player, which may be empty
+   * @return the player instance, if connected, else {@code null}
    */
-  Optional<Player> getPlayer(UUID uuid);
+  @Nullable Player player(UUID uuid);
 
   /**
    * Retrieves all players currently connected to this proxy. This call may or may not be a snapshot
@@ -82,7 +81,7 @@ public interface ProxyServer extends Audience {
    * @param name the name of the server
    * @return the registered server, which may be empty
    */
-  Optional<RegisteredServer> server(String name);
+  @Nullable RegisteredServer server(String name);
 
   /**
    * Retrieves all {@link RegisteredServer}s registered with this proxy.

api/src/main/java/com/velocitypowered/api/proxy/config/ProxyConfig.java

@@ -11,7 +11,7 @@ import com.velocitypowered.api.proxy.ProxyServer;
 import com.velocitypowered.api.util.Favicon;
 import java.util.List;
 import java.util.Map;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Exposes certain proxy configuration information that plugins may use.
@@ -126,7 +126,7 @@ public interface ProxyConfig {
    *
    * @return optional favicon
    */
-  Optional<Favicon> getFavicon();
+  @Nullable Favicon getFavicon();
 
   /**
    * Get whether this proxy displays that it supports Forge/FML.

api/src/main/java/com/velocitypowered/api/proxy/connection/InboundConnection.java

@@ -10,7 +10,7 @@ package com.velocitypowered.api.proxy.connection;
 import com.velocitypowered.api.network.ProtocolVersion;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Represents an incoming connection to the proxy.
@@ -29,7 +29,7 @@ public interface InboundConnection {
    *
    * @return the hostname from the client
    */
-  Optional<InetSocketAddress> connectedHostname();
+  @Nullable InetSocketAddress connectedHostname();
 
   /**
    * Determine whether or not the player remains online.

api/src/main/java/com/velocitypowered/api/proxy/connection/Player.java

@@ -19,10 +19,10 @@ import com.velocitypowered.api.proxy.server.RegisteredServer;
 import com.velocitypowered.api.util.GameProfile;
 import com.velocitypowered.api.util.ModInfo;
 import java.util.List;
-import java.util.Optional;
 import java.util.UUID;
 import net.kyori.adventure.identity.Identified;
 import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Represents a player who is connected to the proxy.
@@ -47,9 +47,10 @@ public interface Player extends CommandSource, Identified, InboundConnection,
   /**
    * Returns the server that the player is currently connected to.
    *
-   * @return an {@link Optional} the server that the player is connected to, which may be empty
+   * @return the server that the player is connected to, which could be {@code null} if no
+   *         connection was made yet (or the player is switching servers)
    */
-  Optional<ServerConnection> connectedServer();
+  @Nullable ServerConnection connectedServer();
 
   /**
    * Returns the player's client settings.
@@ -61,9 +62,9 @@ public interface Player extends CommandSource, Identified, InboundConnection,
   /**
    * Returns the player's mod info if they have a modded client.
    *
-   * @return an {@link Optional} the mod info. which may be empty
+   * @return an the mod info. which may be {@code null} if no info is available
    */
-  Optional<ModInfo> modInfo();
+  @Nullable ModInfo modInfo();
 
   /**
    * Returns the current player's ping.

api/src/main/java/com/velocitypowered/api/proxy/player/ConnectionRequestBuilder.java

@@ -9,9 +9,9 @@ package com.velocitypowered.api.proxy.player;
 
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
-import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import net.kyori.adventure.text.Component;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 /**
  * Provides a fluent interface to send a connection request to another server on the proxy. A
@@ -76,7 +76,7 @@ public interface ConnectionRequestBuilder {
      *
      * @return the reason why the user could not connect to the server
      */
-    Optional<Component> failureReason();
+    @Nullable Component failureReason();
 
     /**
      * Returns the server we actually tried to connect to.

api/src/main/java/com/velocitypowered/api/proxy/player/TabList.java

@@ -10,7 +10,6 @@ package com.velocitypowered.api.proxy.player;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.util.GameProfile;
 import java.util.Collection;
-import java.util.Optional;
 import java.util.UUID;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -45,10 +44,9 @@ public interface TabList {
    * the specified {@link UUID}.
    *
    * @param uuid of the entry
-   * @return {@link Optional} containing the removed {@link TabListEntry} if present, otherwise
-   * {@link Optional#empty()}
+   * @return the removed {@link TabListEntry} if present, otherwise {@code null}
    */
-  Optional<TabListEntry> removeEntry(UUID uuid);
+  @Nullable TabListEntry removeEntry(UUID uuid);
 
   /**
    * Determines if the specified entry exists in the tab list.

api/src/main/java/com/velocitypowered/api/proxy/player/TabListEntry.java

@@ -8,7 +8,6 @@
 package com.velocitypowered.api.proxy.player;
 
 import com.velocitypowered.api.util.GameProfile;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -34,18 +33,17 @@ public interface TabListEntry {
   GameProfile gameProfile();
 
   /**
-   * Returns {@link Optional} text {@link Component}, which if present is the text
+   * Returns an optional text {@link Component}, which if present is the text
    * displayed for {@code this} entry in the {@link TabList}, otherwise
-   * {@link GameProfile#getName()} is shown.
+   * {@link GameProfile#name()} is shown.
    *
-   * @return {@link Optional} text {@link Component} of name displayed in the tab
-   *         list
+   * @return text {@link Component} of name displayed in the tab list
    */
-  Optional<Component> displayName();
+  @Nullable Component displayName();
 
   /**
    * Sets the text {@link Component} to be displayed for {@code this} {@link TabListEntry}. If
-   * {@code null}, {@link GameProfile#getName()} will be shown.
+   * {@code null}, {@link GameProfile#name()} will be shown.
    *
    * @param displayName to show in the {@link TabList} for {@code this} entry
    * @return {@code this}, for chaining

api/src/main/java/com/velocitypowered/api/proxy/server/QueryResponse.java

@@ -18,7 +18,6 @@ import java.util.Arrays;
 import java.util.Collection;
 import java.util.List;
 import java.util.Objects;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.MonotonicNonNull;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -423,8 +422,8 @@ public final class QueryResponse {
       return name;
     }
 
-    public Optional<String> getVersion() {
-      return Optional.ofNullable(version);
+    public @Nullable String getVersion() {
+      return version;
     }
 
     public static PluginInformation of(String name, @Nullable String version) {

api/src/main/java/com/velocitypowered/api/proxy/server/ServerPing.java

@@ -16,7 +16,6 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.List;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.UUID;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.Nullable;
@@ -60,20 +59,20 @@ public final class ServerPing {
     return version;
   }
 
-  public Optional<Players> players() {
-    return Optional.ofNullable(players);
+  public @Nullable Players players() {
+    return players;
   }
 
   public Component description() {
     return description;
   }
 
-  public Optional<Favicon> favicon() {
-    return Optional.ofNullable(favicon);
+  public @Nullable Favicon favicon() {
+    return favicon;
   }
 
-  public Optional<ModInfo> modInfo() {
-    return Optional.ofNullable(modinfo);
+  public @Nullable ModInfo modInfo() {
+    return modinfo;
   }
 
   @Override
@@ -271,12 +270,12 @@ public final class ServerPing {
       return samplePlayers;
     }
 
-    public Optional<Component> getDescription() {
-      return Optional.ofNullable(description);
+    public @Nullable Component getDescription() {
+      return description;
     }
 
-    public Optional<Favicon> getFavicon() {
-      return Optional.ofNullable(favicon);
+    public @Nullable Favicon getFavicon() {
+      return favicon;
     }
 
     public String getModType() {

api/src/main/java/com/velocitypowered/api/util/GameProfile.java

@@ -11,11 +11,15 @@ import com.google.common.base.Preconditions;
 import com.google.common.collect.ImmutableList;
 import java.util.List;
 import java.util.UUID;
+import net.kyori.adventure.identity.Identified;
+import net.kyori.adventure.identity.Identity;
+import org.checkerframework.checker.nullness.qual.NonNull;
+import org.jetbrains.annotations.NotNull;
 
 /**
  * Represents a Mojang game profile. This class is immutable.
  */
-public final class GameProfile {
+public final class GameProfile implements Identified, Identity {
 
   private final UUID id;
   private final String undashedId;
@@ -55,7 +59,7 @@ public final class GameProfile {
    * Returns the undashed, Mojang-style UUID.
    * @return the undashed UUID
    */
-  public String getUndashedId() {
+  public String undashedId() {
     return undashedId;
   }
 
@@ -63,7 +67,8 @@ public final class GameProfile {
    * Returns the UUID associated with this game profile.
    * @return the UUID
    */
-  public UUID getId() {
+  @Override
+  public @NotNull UUID uuid() {
     return id;
   }
 
@@ -71,7 +76,7 @@ public final class GameProfile {
    * Returns the username associated with this profile.
    * @return the username
    */
-  public String getName() {
+  public String name() {
     return name;
   }
 
@@ -79,7 +84,7 @@ public final class GameProfile {
    * Returns an immutable list of profile properties associated with this profile.
    * @return the properties associated with this profile
    */
-  public List<Property> getProperties() {
+  public List<Property> properties() {
     return properties;
   }
 
@@ -89,7 +94,7 @@ public final class GameProfile {
    * @param id the new unique id
    * @return the new {@code GameProfile}
    */
-  public GameProfile withId(UUID id) {
+  public GameProfile withUuid(UUID id) {
     return new GameProfile(Preconditions.checkNotNull(id, "id"), UuidUtils.toUndashed(id),
         this.name, this.properties);
   }
@@ -172,6 +177,11 @@ public final class GameProfile {
         + '}';
   }
 
+  @Override
+  public @NonNull Identity identity() {
+    return this;
+  }
+
   /**
    * Represents a Mojang profile property. Just like {@link GameProfile}, this class is immutable.
    */
@@ -193,15 +203,15 @@ public final class GameProfile {
       this.signature = Preconditions.checkNotNull(signature, "signature");
     }
 
-    public String getName() {
+    public String name() {
       return name;
     }
 
-    public String getValue() {
+    public String value() {
       return value;
     }
 
-    public String getSignature() {
+    public String signature() {
       return signature;
     }
 

proxy/src/main/java/com/velocitypowered/proxy/VelocityServer.java

@@ -333,7 +333,7 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
           eventManager.registerInternally(plugin, instance.get());
         } catch (Exception e) {
           logger.error("Unable to register plugin listener for {}",
-              plugin.description().name().orElse(plugin.description().id()), e);
+              MoreObjects.firstNonNull(plugin.description().name(), plugin.description().id()), e);
         }
       }
     }
@@ -373,18 +373,18 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
     for (Map.Entry<String, String> entry : newConfiguration.getServers().entrySet()) {
       ServerInfo newInfo =
           new ServerInfo(entry.getKey(), AddressUtil.parseAddress(entry.getValue()));
-      Optional<RegisteredServer> rs = servers.getServer(entry.getKey());
-      if (!rs.isPresent()) {
+      RegisteredServer rs = servers.getServer(entry.getKey());
+      if (rs == null) {
         servers.register(newInfo);
-      } else if (!rs.get().serverInfo().equals(newInfo)) {
-        for (Player player : rs.get().connectedPlayers()) {
+      } else if (!rs.serverInfo().equals(newInfo)) {
+        for (Player player : rs.connectedPlayers()) {
           if (!(player instanceof ConnectedPlayer)) {
             throw new IllegalStateException("ConnectedPlayer not found for player " + player
-                + " in server " + rs.get().serverInfo().name());
+                + " in server " + rs.serverInfo().name());
           }
           evacuate.add((ConnectedPlayer) player);
         }
-        servers.unregister(rs.get().serverInfo());
+        servers.unregister(rs.serverInfo());
         servers.register(newInfo);
       }
     }
@@ -393,9 +393,9 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
     if (!evacuate.isEmpty()) {
       CountDownLatch latch = new CountDownLatch(evacuate.size());
       for (ConnectedPlayer player : evacuate) {
-        Optional<RegisteredServer> next = player.getNextServerToTry();
-        if (next.isPresent()) {
-          player.createConnectionRequest(next.get()).connectWithIndication()
+        RegisteredServer next = player.getNextServerToTry();
+        if (next != null) {
+          player.createConnectionRequest(next).connectWithIndication()
               .whenComplete((success, ex) -> {
                 if (ex != null || success == null || !success) {
                   player.disconnect(Component.text("Your server has been changed, but we could "
@@ -613,15 +613,15 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
   }
 
   @Override
-  public Optional<Player> getPlayer(String username) {
+  public @Nullable Player player(String username) {
     Preconditions.checkNotNull(username, "username");
-    return Optional.ofNullable(connectionsByName.get(username.toLowerCase(Locale.US)));
+    return connectionsByName.get(username.toLowerCase(Locale.US));
   }
 
   @Override
-  public Optional<Player> getPlayer(UUID uuid) {
+  public @Nullable Player player(UUID uuid) {
     Preconditions.checkNotNull(uuid, "uuid");
-    return Optional.ofNullable(connectionsByUuid.get(uuid));
+    return connectionsByUuid.get(uuid);
   }
 
   @Override
@@ -653,7 +653,7 @@ public class VelocityServer implements ProxyServer, ForwardingAudience {
   }
 
   @Override
-  public Optional<RegisteredServer> server(String name) {
+  public @Nullable RegisteredServer server(String name) {
     return servers.getServer(name);
   }
 

proxy/src/main/java/com/velocitypowered/proxy/command/VelocityCommandManager.java

@@ -17,6 +17,7 @@
 
 package com.velocitypowered.proxy.command;
 
+import com.google.common.base.MoreObjects;
 import com.google.common.base.Preconditions;
 import com.google.common.collect.Lists;
 import com.mojang.brigadier.CommandDispatcher;
@@ -164,7 +165,8 @@ public class VelocityCommandManager implements CommandManager {
       if (commandResult.isForwardToServer() || !commandResult.isAllowed()) {
         return false;
       }
-      return executeImmediately0(source, commandResult.modifiedCommand().orElse(event.rawCommand()));
+      return executeImmediately0(source,
+          MoreObjects.firstNonNull(commandResult.modifiedCommand(), event.rawCommand()));
     }, eventManager.getAsyncExecutor());
   }
 

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/GlistCommand.java

@@ -33,7 +33,6 @@ import com.velocitypowered.api.proxy.ProxyServer;
 import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 import java.util.List;
-import java.util.Optional;
 import net.kyori.adventure.identity.Identity;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.TextComponent;
@@ -92,13 +91,13 @@ public class GlistCommand {
       }
       sendTotalProxyCount(source);
     } else {
-      Optional<RegisteredServer> registeredServer = server.server(serverName);
-      if (!registeredServer.isPresent()) {
+      RegisteredServer registeredServer = server.server(serverName);
+      if (registeredServer == null) {
         source.sendMessage(Identity.nil(),
             CommandMessages.SERVER_DOES_NOT_EXIST.args(Component.text(serverName)));
         return -1;
       }
-      sendServerPlayers(source, registeredServer.get(), false);
+      sendServerPlayers(source, registeredServer, false);
     }
     return 1;
   }

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/ServerCommand.java

@@ -62,21 +62,22 @@ public class ServerCommand implements SimpleCommand {
     if (args.length == 1) {
       // Trying to connect to a server.
       String serverName = args[0];
-      Optional<RegisteredServer> toConnect = server.server(serverName);
-      if (!toConnect.isPresent()) {
+      RegisteredServer toConnect = server.server(serverName);
+      if (toConnect == null) {
         player.sendMessage(Identity.nil(), CommandMessages.SERVER_DOES_NOT_EXIST
             .args(Component.text(serverName)));
         return;
       }
 
-      player.createConnectionRequest(toConnect.get()).fireAndForget();
+      player.createConnectionRequest(toConnect).fireAndForget();
     } else {
       outputServerInformation(player);
     }
   }
 
   private void outputServerInformation(Player executor) {
-    String currentServer = executor.connectedServer().map(ServerConnection::serverInfo)
+    String currentServer = Optional.ofNullable(executor.connectedServer())
+        .map(ServerConnection::serverInfo)
         .map(ServerInfo::name).orElse("<unknown>");
     executor.sendMessage(Identity.nil(), Component.translatable(
         "velocity.command.server-current-server",

proxy/src/main/java/com/velocitypowered/proxy/command/builtin/VelocityCommand.java

@@ -44,7 +44,6 @@ import java.util.Collection;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
-import java.util.concurrent.ExecutionException;
 import java.util.stream.Collectors;
 import net.kyori.adventure.identity.Identity;
 import net.kyori.adventure.text.Component;
@@ -295,17 +294,17 @@ public class VelocityCommand implements SimpleCommand {
     }
 
     private TextComponent componentForPlugin(PluginDescription description) {
-      String pluginInfo = description.name().orElse(description.id())
-          + description.version().map(v -> " " + v).orElse("");
+      String pluginInfo = description.name();
 
       TextComponent.Builder hoverText = Component.text().content(pluginInfo);
 
-      description.url().ifPresent(url -> {
+      String pluginUrl = description.url();
+      if (pluginUrl != null) {
         hoverText.append(Component.newline());
         hoverText.append(Component.translatable(
             "velocity.command.plugin-tooltip-website",
-            Component.text(url)));
-      });
+            Component.text(pluginUrl)));
+      }
       if (!description.authors().isEmpty()) {
         hoverText.append(Component.newline());
         if (description.authors().size() == 1) {
@@ -319,11 +318,13 @@ public class VelocityCommand implements SimpleCommand {
           );
         }
       }
-      description.description().ifPresent(pdesc -> {
+
+      String humanDescription = description.description();
+      if (humanDescription != null) {
         hoverText.append(Component.newline());
         hoverText.append(Component.newline());
-        hoverText.append(Component.text(pdesc));
-      });
+        hoverText.append(Component.text(humanDescription));
+      }
 
       return Component.text(description.id(), NamedTextColor.GRAY)
           .hoverEvent(HoverEvent.showText(hoverText.build()));

proxy/src/main/java/com/velocitypowered/proxy/config/VelocityConfiguration.java

@@ -44,7 +44,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
-import java.util.Optional;
 import java.util.Random;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
@@ -315,8 +314,8 @@ public class VelocityConfiguration implements ProxyConfig {
   }
 
   @Override
-  public Optional<Favicon> getFavicon() {
-    return Optional.ofNullable(favicon);
+  public @Nullable Favicon getFavicon() {
+    return favicon;
   }
 
   @Override

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

@@ -179,7 +179,8 @@ public class MinecraftConnection extends ChannelInboundHandlerAdapter {
               || sessionHandler instanceof HandshakeSessionHandler
               || sessionHandler instanceof StatusSessionHandler;
           boolean isQuietDecoderException = cause instanceof QuietDecoderException;
-          boolean willLog = !isQuietDecoderException && !frontlineHandler;
+          boolean willLog = MinecraftDecoder.DEBUG
+              || (!isQuietDecoderException && !frontlineHandler);
           if (willLog) {
             logger.error("{}: exception encountered in {}", association, sessionHandler, cause);
           } else {

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

@@ -37,7 +37,6 @@ import io.netty.buffer.Unpooled;
 import io.netty.channel.unix.DomainSocketAddress;
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
-import java.util.Optional;
 import java.util.StringJoiner;
 import net.kyori.adventure.identity.Identity;
 import net.kyori.adventure.key.Key;
@@ -69,18 +68,20 @@ public class BungeeCordMessageResponder {
 
   private void processConnect(ByteBufDataInput in) {
     String serverName = in.readUTF();
-    proxy.server(serverName).ifPresent(server -> player.createConnectionRequest(server)
-        .fireAndForget());
+    RegisteredServer server = proxy.server(serverName);
+    if (server != null) {
+      player.createConnectionRequest(server).fireAndForget();
+    }
   }
 
   private void processConnectOther(ByteBufDataInput in) {
     String playerName = in.readUTF();
     String serverName = in.readUTF();
 
-    Optional<Player> referencedPlayer = proxy.getPlayer(playerName);
-    Optional<RegisteredServer> referencedServer = proxy.server(serverName);
-    if (referencedPlayer.isPresent() && referencedServer.isPresent()) {
-      referencedPlayer.get().createConnectionRequest(referencedServer.get()).fireAndForget();
+    Player referencedPlayer = proxy.player(playerName);
+    RegisteredServer referencedServer = proxy.server(serverName);
+    if (referencedPlayer != null && referencedServer != null) {
+      referencedPlayer.createConnectionRequest(referencedServer).fireAndForget();
     }
   }
 
@@ -111,12 +112,13 @@ public class BungeeCordMessageResponder {
       out.writeUTF("ALL");
       out.writeInt(proxy.countConnectedPlayers());
     } else {
-      proxy.server(target).ifPresent(rs -> {
-        int playersOnServer = rs.connectedPlayers().size();
+      RegisteredServer referencedServer = proxy.server(target);
+      if (referencedServer != null) {
+        int playersOnServer = referencedServer.connectedPlayers().size();
         out.writeUTF("PlayerCount");
-        out.writeUTF(rs.serverInfo().name());
+        out.writeUTF(referencedServer.serverInfo().name());
         out.writeInt(playersOnServer);
-      });
+      }
     }
 
     if (buf.isReadable()) {
@@ -141,16 +143,17 @@ public class BungeeCordMessageResponder {
       }
       out.writeUTF(joiner.toString());
     } else {
-      proxy.server(target).ifPresent(info -> {
+      RegisteredServer referencedServer = proxy.server(target);
+      if (referencedServer != null) {
         out.writeUTF("PlayerList");
-        out.writeUTF(info.serverInfo().name());
+        out.writeUTF(referencedServer.serverInfo().name());
 
         StringJoiner joiner = new StringJoiner(", ");
-        for (Player online : info.connectedPlayers()) {
+        for (Player online : referencedServer.connectedPlayers()) {
           joiner.add(online.username());
         }
         out.writeUTF(joiner.toString());
-      });
+      }
     }
 
     if (buf.isReadable()) {
@@ -191,8 +194,10 @@ public class BungeeCordMessageResponder {
     if (target.equals("ALL")) {
       proxy.sendMessage(Identity.nil(), messageComponent);
     } else {
-      proxy.getPlayer(target).ifPresent(player -> player.sendMessage(Identity.nil(),
-          messageComponent));
+      Player player = proxy.player(target);
+      if (player != null) {
+        player.sendMessage(Identity.nil(), messageComponent);
+      }
     }
   }
 
@@ -217,7 +222,8 @@ public class BungeeCordMessageResponder {
   }
 
   private void processUuidOther(ByteBufDataInput in) {
-    proxy.getPlayer(in.readUTF()).ifPresent(player -> {
+    Player player = proxy.player(in.readUTF());
+    if (player != null) {
       ByteBuf buf = Unpooled.buffer();
       ByteBufDataOutput out = new ByteBufDataOutput(buf);
 
@@ -226,11 +232,12 @@ public class BungeeCordMessageResponder {
       out.writeUTF(UuidUtils.toUndashed(player.id()));
 
       sendResponseOnConnection(buf);
-    });
+    }
   }
 
   private void processIpOther(ByteBufDataInput in) {
-    proxy.getPlayer(in.readUTF()).ifPresent(player -> {
+    Player player = proxy.player(in.readUTF());
+    if (player != null) {
       ByteBuf buf = Unpooled.buffer();
       ByteBufDataOutput out = new ByteBufDataOutput(buf);
 
@@ -247,11 +254,12 @@ public class BungeeCordMessageResponder {
       }
 
       sendResponseOnConnection(buf);
-    });
+    }
   }
 
   private void processServerIp(ByteBufDataInput in) {
-    proxy.server(in.readUTF()).ifPresent(info -> {
+    RegisteredServer info = proxy.server(in.readUTF());
+    if (info != null) {
       ByteBuf buf = Unpooled.buffer();
       ByteBufDataOutput out = new ByteBufDataOutput(buf);
 
@@ -268,21 +276,22 @@ public class BungeeCordMessageResponder {
       }
 
       sendResponseOnConnection(buf);
-    });
+    }
   }
 
   private void processKick(ByteBufDataInput in) {
-    proxy.getPlayer(in.readUTF()).ifPresent(player -> {
+    Player player = proxy.player(in.readUTF());
+    if (player != null) {
       String kickReason = in.readUTF();
       player.disconnect(LegacyComponentSerializer.legacySection().deserialize(kickReason));
-    });
+    }
   }
 
   private void processForwardToPlayer(ByteBufDataInput in) {
-    Optional<Player> player = proxy.getPlayer(in.readUTF());
-    if (player.isPresent()) {
+    Player player = proxy.player(in.readUTF());
+    if (player != null) {
       ByteBuf toForward = in.unwrap().copy();
-      sendServerResponse((ConnectedPlayer) player.get(), toForward);
+      sendServerResponse((ConnectedPlayer) player, toForward);
     }
   }
 
@@ -299,9 +308,9 @@ public class BungeeCordMessageResponder {
         toForward.release();
       }
     } else {
-      Optional<RegisteredServer> server = proxy.server(target);
-      if (server.isPresent()) {
-        ((VelocityRegisteredServer) server.get()).sendPluginMessage(CHANNEL, toForward);
+      RegisteredServer server = proxy.server(target);
+      if (server != null) {
+        ((VelocityRegisteredServer) server).sendPluginMessage(CHANNEL, toForward);
       } else {
         toForward.release();
       }

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

@@ -168,9 +168,9 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
     try {
       ProtocolUtils.writeVarInt(forwarded, VelocityConstants.FORWARDING_VERSION);
       ProtocolUtils.writeString(forwarded, address);
-      ProtocolUtils.writeUuid(forwarded, profile.getId());
-      ProtocolUtils.writeString(forwarded, profile.getName());
-      ProtocolUtils.writeProperties(forwarded, profile.getProperties());
+      ProtocolUtils.writeUuid(forwarded, profile.uuid());
+      ProtocolUtils.writeString(forwarded, profile.name());
+      ProtocolUtils.writeProperties(forwarded, profile.properties());
 
       SecretKey key = new SecretKeySpec(hmacSecret, "HmacSHA256");
       Mac mac = Mac.getInstance("HmacSHA256");

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

@@ -119,7 +119,8 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
   }
 
   private String playerConnectedHostname() {
-    return proxyPlayer.connectedHostname().map(InetSocketAddress::getHostString).orElse("");
+    InetSocketAddress vhost = proxyPlayer.connectedHostname();
+    return vhost == null ? "" : vhost.getHostString();
   }
 
   private String createLegacyForwardingAddress(UnaryOperator<List<Property>> propertiesTransform) {
@@ -135,10 +136,10 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
         .append('\0')
         .append(((InetSocketAddress) proxyPlayer.remoteAddress()).getHostString())
         .append('\0')
-        .append(proxyPlayer.gameProfile().getUndashedId())
+        .append(proxyPlayer.gameProfile().undashedId())
         .append('\0');
     GENERAL_GSON
-        .toJson(propertiesTransform.apply(proxyPlayer.gameProfile().getProperties()), data);
+        .toJson(propertiesTransform.apply(proxyPlayer.gameProfile().properties()), data);
     return data.toString();
   }
 
@@ -233,7 +234,7 @@ public class VelocityServerConnection implements MinecraftConnectionAssociation,
 
   @Override
   public String toString() {
-    return "[server connection] " + proxyPlayer.gameProfile().getName() + " -> "
+    return "[server connection] " + proxyPlayer.gameProfile().name() + " -> "
         + registeredServer.serverInfo().name();
   }
 

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

@@ -22,6 +22,7 @@ import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_16;
 import static com.velocitypowered.api.network.ProtocolVersion.MINECRAFT_1_8;
 import static com.velocitypowered.proxy.network.PluginMessageUtil.constructChannelsPacket;
 
+import com.google.common.base.MoreObjects;
 import com.google.common.collect.ImmutableList;
 import com.velocitypowered.api.event.command.CommandExecuteEvent.CommandResult;
 import com.velocitypowered.api.event.connection.PluginMessageEvent;
@@ -65,7 +66,6 @@ import java.util.ArrayDeque;
 import java.util.ArrayList;
 import java.util.Collection;
 import java.util.List;
-import java.util.Optional;
 import java.util.Queue;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
@@ -598,7 +598,7 @@ public class ClientPlaySessionHandler implements MinecraftSessionHandler {
     }
 
     MinecraftConnection smc = player.ensureAndGetCurrentServer().ensureConnected();
-    String commandToRun = result.modifiedCommand().orElse(originalCommand);
+    String commandToRun = MoreObjects.firstNonNull(result.modifiedCommand(), originalCommand);
     if (result.isForwardToServer()) {
       return CompletableFuture.runAsync(() -> smc.write(new ServerboundChatPacket("/"
           + commandToRun)), smc.eventLoop());

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

@@ -81,7 +81,6 @@ import java.util.Collections;
 import java.util.List;
 import java.util.Locale;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.CompletionException;
@@ -162,17 +161,17 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
 
   @Override
   public String username() {
-    return profile.getName();
+    return profile.name();
   }
 
   @Override
   public UUID id() {
-    return profile.getId();
+    return profile.uuid();
   }
 
   @Override
-  public Optional<ServerConnection> connectedServer() {
-    return Optional.ofNullable(connectedServer);
+  public @Nullable ServerConnection connectedServer() {
+    return connectedServer;
   }
 
   /**
@@ -222,8 +221,8 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
   }
 
   @Override
-  public Optional<ModInfo> modInfo() {
-    return Optional.ofNullable(modInfo);
+  public @Nullable ModInfo modInfo() {
+    return modInfo;
   }
 
   public void setModInfo(ModInfo modInfo) {
@@ -237,8 +236,8 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
   }
 
   @Override
-  public Optional<InetSocketAddress> connectedHostname() {
-    return Optional.ofNullable(virtualHost);
+  public @Nullable InetSocketAddress connectedHostname() {
+    return virtualHost;
   }
 
   void setPermissionFunction(PermissionFunction permissionFunction) {
@@ -509,9 +508,12 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
     boolean kickedFromCurrent = connectedServer == null || connectedServer.target().equals(rs);
     ServerKickResult result;
     if (kickedFromCurrent) {
-      Optional<RegisteredServer> next = getNextServerToTry(rs);
-      result = next.map(RedirectPlayer::create)
-          .orElseGet(() -> DisconnectPlayer.create(friendlyReason));
+      RegisteredServer next = getNextServerToTry(rs);
+      if (next == null) {
+        result = DisconnectPlayer.create(friendlyReason);
+      } else {
+        result = RedirectPlayer.create(next);
+      }
     } else {
       // If we were kicked by going to another server, the connection should not be in flight
       if (connectionInFlight != null && connectionInFlight.target().equals(rs)) {
@@ -562,11 +564,12 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
                     case CONNECTION_IN_PROGRESS:
                     // Fatal case
                     case CONNECTION_CANCELLED:
-                      disconnect(status.failureReason().orElse(res.message()));
+                      disconnect(status.failureReason() != null ? status.failureReason()
+                          : res.message());
                       break;
                     case SERVER_DISCONNECTED:
-                      Component reason = status.failureReason()
-                          .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
+                      Component reason = status.failureReason() != null ? status.failureReason()
+                          : ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR;
                       handleConnectionException(res.getServer(), ClientboundDisconnectPacket.create(reason,
                           protocolVersion()), ((Impl) status).isSafe());
                       break;
@@ -601,7 +604,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
    *
    * @return the next server to try
    */
-  public Optional<RegisteredServer> getNextServerToTry() {
+  public @Nullable RegisteredServer getNextServerToTry() {
     return this.getNextServerToTry(null);
   }
 
@@ -613,11 +616,10 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
    *
    * @return the next server to try
    */
-  private Optional<RegisteredServer> getNextServerToTry(@Nullable RegisteredServer current) {
+  private @Nullable RegisteredServer getNextServerToTry(@Nullable RegisteredServer current) {
     if (serversToTry == null) {
-      String virtualHostStr = connectedHostname().map(InetSocketAddress::getHostString)
-          .orElse("")
-          .toLowerCase(Locale.ROOT);
+      InetSocketAddress vhost = connectedHostname();
+      String virtualHostStr = vhost == null ? "" : vhost.getHostString().toLowerCase(Locale.ROOT);
       serversToTry = server.configuration().getForcedHosts().getOrDefault(virtualHostStr,
           Collections.emptyList());
     }
@@ -637,7 +639,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
       tryIndex = i;
       return server.server(toTryName);
     }
-    return Optional.empty();
+    return null;
   }
 
   private static boolean hasSameName(RegisteredServer server, String name) {
@@ -684,15 +686,15 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
       connectedServer.disconnect();
     }
 
-    Optional<Player> connectedPlayer = server.getPlayer(this.id());
+    Player connectedPlayer = server.player(this.id());
     server.unregisterConnection(this);
 
     DisconnectEventImpl.LoginStatus status;
-    if (connectedPlayer.isPresent()) {
-      if (!connectedPlayer.get().connectedServer().isPresent()) {
+    if (connectedPlayer != null) {
+      if (connectedPlayer.connectedServer() != null) {
         status = LoginStatus.PRE_SERVER_JOIN;
       } else {
-        status = connectedPlayer.get() == this ? LoginStatus.SUCCESSFUL_LOGIN
+        status = connectedPlayer == this ? LoginStatus.SUCCESSFUL_LOGIN
             : LoginStatus.CONFLICTING_LOGIN;
       }
     } else {
@@ -716,7 +718,7 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
 
   @Override
   public String toString() {
-    return "[connected player] " + profile.getName() + " (" + remoteAddress() + ")";
+    return "[connected player] " + profile.name() + " (" + remoteAddress() + ")";
   }
 
   @Override
@@ -847,45 +849,44 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
       return toConnect;
     }
 
-    private Optional<ConnectionRequestBuilder.Status> checkServer(RegisteredServer server) {
+    private ConnectionRequestBuilder.@Nullable Status checkServer(RegisteredServer server) {
       Preconditions.checkArgument(server instanceof VelocityRegisteredServer,
           "Not a valid Velocity server.");
       if (connectionInFlight != null || (connectedServer != null
           && !connectedServer.hasCompletedJoin())) {
-        return Optional.of(ConnectionRequestBuilder.Status.CONNECTION_IN_PROGRESS);
+        return ConnectionRequestBuilder.Status.CONNECTION_IN_PROGRESS;
       }
       if (connectedServer != null && connectedServer.target().equals(server)) {
-        return Optional.of(ALREADY_CONNECTED);
+        return ALREADY_CONNECTED;
       }
-      return Optional.empty();
+      return null;
     }
 
-    private CompletableFuture<Optional<Status>> getInitialStatus() {
+    private CompletableFuture<ConnectionRequestBuilder.Status> getInitialStatus() {
       return CompletableFuture.supplyAsync(() -> checkServer(toConnect), connection.eventLoop());
     }
 
     private CompletableFuture<Impl> internalConnect() {
       return this.getInitialStatus()
           .thenCompose(initialCheck -> {
-            if (initialCheck.isPresent()) {
-              return completedFuture(plainResult(initialCheck.get(), toConnect));
+            if (initialCheck != null) {
+              return completedFuture(plainResult(initialCheck, toConnect));
             }
 
             ServerPreConnectEvent event = new ServerPreConnectEventImpl(ConnectedPlayer.this,
                 toConnect);
             return server.eventManager().fire(event)
                 .thenComposeAsync(newEvent -> {
-                  Optional<RegisteredServer> newDest = newEvent.result().target();
-                  if (!newDest.isPresent()) {
+                  RegisteredServer realDestination = newEvent.result().target();
+                  if (realDestination == null) {
                     return completedFuture(
                         plainResult(ConnectionRequestBuilder.Status.CONNECTION_CANCELLED, toConnect)
                     );
                   }
 
-                  RegisteredServer realDestination = newDest.get();
-                  Optional<ConnectionRequestBuilder.Status> check = checkServer(realDestination);
-                  if (check.isPresent()) {
-                    return completedFuture(plainResult(check.get(), realDestination));
+                  ConnectionRequestBuilder.Status secondCheck = checkServer(realDestination);
+                  if (secondCheck != null) {
+                    return completedFuture(plainResult(secondCheck, realDestination));
                   }
 
                   VelocityRegisteredServer vrs = (VelocityRegisteredServer) realDestination;
@@ -945,8 +946,8 @@ public class ConnectedPlayer implements MinecraftConnectionAssociation, Player {
                 // Ignored; the plugin probably already handled this.
                 break;
               case SERVER_DISCONNECTED:
-                Component reason = status.failureReason()
-                    .orElse(ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR);
+                Component reason = status.failureReason() != null ? status.failureReason()
+                    : ConnectionMessages.INTERNAL_SERVER_CONNECTION_ERROR;
                 handleConnectionException(toConnect, ClientboundDisconnectPacket.create(reason,
                     protocolVersion()), status.isSafe());
                 break;

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

@@ -40,7 +40,6 @@ import io.netty.buffer.ByteBuf;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
 import java.util.Objects;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.format.NamedTextColor;
 import org.apache.logging.log4j.LogManager;
@@ -88,11 +87,11 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
       LOGGER.error("{} provided invalid protocol {}", ic, handshake.getNextStatus());
       connection.close(true);
     } else {
-      connection.setState(nextState);
       connection.setProtocolVersion(handshake.getProtocolVersion());
       connection.setAssociation(ic);
 
       if (nextState == ProtocolStates.STATUS) {
+        connection.setState(nextState);
         connection.setSessionHandler(new StatusSessionHandler(server, connection, ic));
       } else if (nextState == ProtocolStates.LOGIN) {
         this.handleLogin(handshake, ic);
@@ -134,12 +133,15 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     }
 
     connection.setAutoReading(false);
+    connection.setState(ProtocolStates.LOGIN);
     server.eventManager().fire(new ConnectionHandshakeEventImpl(ic, handshake.getServerAddress()))
         .thenAcceptAsync(event -> {
-          connection.setAutoReading(true);
+          if (connection.isClosed()) {
+            return;
+          }
 
           if (!event.result().isAllowed()) {
-            ic.disconnectQuietly(event.result().reason().get());
+            ic.disconnectQuietly(event.result().reason());
           } else {
             // if the handshake is changed, propagate the change
             if (!event.currentHostname().equals(event.originalHostname())) {
@@ -161,6 +163,7 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
             }
 
             connection.setSessionHandler(new LoginSessionHandler(server, connection, ic));
+            connection.setAutoReading(true);
           }
         }, connection.eventLoop());
   }
@@ -234,8 +237,8 @@ public class HandshakeSessionHandler implements MinecraftSessionHandler {
     }
 
     @Override
-    public Optional<InetSocketAddress> connectedHostname() {
-      return Optional.ofNullable(ping.getVhost());
+    public @Nullable InetSocketAddress connectedHostname() {
+      return ping.getVhost();
     }
 
     @Override

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

@@ -27,8 +27,6 @@ import com.velocitypowered.proxy.network.packet.serverbound.ServerboundHandshake
 import java.net.InetSocketAddress;
 import java.net.SocketAddress;
 import java.util.Locale;
-import java.util.Objects;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
 import net.kyori.adventure.translation.GlobalTranslator;
@@ -58,8 +56,8 @@ public final class InitialInboundConnection implements InboundConnection,
   }
 
   @Override
-  public Optional<InetSocketAddress> connectedHostname() {
-    return Optional.of(InetSocketAddress.createUnresolved(cleanedHostname, handshake.getPort()));
+  public @Nullable InetSocketAddress connectedHostname() {
+    return InetSocketAddress.createUnresolved(cleanedHostname, handshake.getPort());
   }
 
   @Override

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

@@ -59,7 +59,6 @@ import java.security.GeneralSecurityException;
 import java.security.KeyPair;
 import java.security.MessageDigest;
 import java.util.Arrays;
-import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
@@ -194,10 +193,10 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
           }
 
           ComponentResult result = event.result();
-          Optional<Component> disconnectReason = result.reason();
-          if (disconnectReason.isPresent()) {
+          Component disconnectReason = result.reason();
+          if (disconnectReason != null) {
             // The component is guaranteed to be provided if the connection was denied.
-            inbound.disconnect(disconnectReason.get());
+            inbound.disconnect(disconnectReason);
             return;
           }
 
@@ -242,7 +241,7 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
 
       // Initiate a regular connection and move over to it.
       ConnectedPlayer player = new ConnectedPlayer(server, profileEvent.gameProfile(),
-          mcConnection, inbound.connectedHostname().orElse(null), onlineMode);
+          mcConnection, inbound.connectedHostname(), onlineMode);
       this.connectedPlayer = player;
       if (!server.canRegisterConnection(player)) {
         player.disconnect0(Component.translatable("velocity.error.already-connected-proxy",
@@ -302,9 +301,9 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
             return;
           }
 
-          Optional<Component> reason = event.result().reason();
-          if (reason.isPresent()) {
-            player.disconnect0(reason.get(), true);
+          Component denialReason = event.result().reason();
+          if (denialReason != null) {
+            player.disconnect0(denialReason, true);
           } else {
             if (!server.registerConnection(player)) {
               player.disconnect0(Component.translatable("velocity.error.already-connected-proxy"),
@@ -328,19 +327,19 @@ public class LoginSessionHandler implements MinecraftSessionHandler {
   }
 
   private CompletableFuture<Void> connectToInitialServer(ConnectedPlayer player) {
-    Optional<RegisteredServer> initialFromConfig = player.getNextServerToTry();
+    RegisteredServer initialFromConfig = player.getNextServerToTry();
     PlayerChooseInitialServerEvent event = new PlayerChooseInitialServerEventImpl(player,
-        initialFromConfig.orElse(null));
+        initialFromConfig);
 
     return server.eventManager().fire(event)
         .thenRunAsync(() -> {
-          Optional<RegisteredServer> toTry = event.initialServer();
-          if (!toTry.isPresent()) {
+          RegisteredServer toTry = event.initialServer();
+          if (toTry == null) {
             player.disconnect0(Component.translatable("velocity.error.no-available-servers",
                 NamedTextColor.RED), true);
             return;
           }
-          player.createConnectionRequest(toTry.get()).fireAndForget();
+          player.createConnectionRequest(toTry).fireAndForget();
         }, mcConnection.eventLoop());
   }
 

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

@@ -43,7 +43,6 @@ import java.net.InetSocketAddress;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
-import java.util.Optional;
 import java.util.concurrent.CompletableFuture;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
@@ -82,7 +81,7 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
         new ServerPing.Players(server.countConnectedPlayers(), configuration.getShowMaxPlayers(),
             ImmutableList.of()),
         configuration.getMotd(),
-        configuration.getFavicon().orElse(null),
+        configuration.getFavicon(),
         configuration.isAnnounceForge() ? ModInfo.DEFAULT : null
     );
   }
@@ -92,11 +91,11 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
     ServerPing fallback = constructLocalPing(pingingVersion);
     List<CompletableFuture<ServerPing>> pings = new ArrayList<>();
     for (String s : servers) {
-      Optional<RegisteredServer> rs = server.server(s);
-      if (!rs.isPresent()) {
+      RegisteredServer rs = server.server(s);
+      if (rs == null) {
         continue;
       }
-      VelocityRegisteredServer vrs = (VelocityRegisteredServer) rs.get();
+      VelocityRegisteredServer vrs = (VelocityRegisteredServer) rs;
       pings.add(vrs.ping(connection.eventLoop(), pingingVersion));
     }
     if (pings.isEmpty()) {
@@ -124,9 +123,9 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
             if (response == fallback) {
               continue;
             }
-            Optional<ModInfo> modInfo = response.modInfo();
-            if (modInfo.isPresent()) {
-              return fallback.asBuilder().mods(modInfo.get()).build();
+            ModInfo modInfo = response.modInfo();
+            if (modInfo != null) {
+              return fallback.asBuilder().mods(modInfo).build();
             }
           }
           return fallback;
@@ -145,10 +144,10 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
 
             return new ServerPing(
                 fallback.version(),
-                fallback.players().orElse(null),
+                fallback.players(),
                 response.description(),
-                fallback.favicon().orElse(null),
-                response.modInfo().orElse(null)
+                fallback.favicon(),
+                response.modInfo()
             );
           }
           return fallback;
@@ -168,9 +167,8 @@ public class StatusSessionHandler implements MinecraftSessionHandler {
     if (passthrough == PingPassthroughMode.DISABLED) {
       return CompletableFuture.completedFuture(constructLocalPing(shownVersion));
     } else {
-      String virtualHostStr = inbound.connectedHostname().map(InetSocketAddress::getHostString)
-          .map(str -> str.toLowerCase(Locale.ROOT))
-          .orElse("");
+      InetSocketAddress vhost = inbound.connectedHostname();
+      String virtualHostStr = vhost == null ? "" : vhost.getHostString().toLowerCase(Locale.ROOT);
       List<String> serversToTry = server.configuration().getForcedHosts().getOrDefault(
           virtualHostStr, server.configuration().getAttemptConnectionOrder());
       return attemptPingPassthrough(configuration.getPingPassthrough(), serversToTry, shownVersion);

proxy/src/main/java/com/velocitypowered/proxy/connection/forge/legacy/LegacyForgeHandshakeClientPhase.java

@@ -93,7 +93,7 @@ public enum LegacyForgeHandshakeClientPhase implements ClientConnectionPhase {
         AbstractPluginMessagePacket<?> message,
         MinecraftConnection backendConn) {
       // Read the mod list if we haven't already.
-      if (!player.modInfo().isPresent()) {
+      if (player.modInfo() == null) {
         List<ModInfo.Mod> mods = LegacyForgeUtil.readModList(message);
         if (!mods.isEmpty()) {
           player.setModInfo(new ModInfo("FML", mods));

proxy/src/main/java/com/velocitypowered/proxy/connection/util/ConnectionRequestResults.java

@@ -21,7 +21,6 @@ import com.velocitypowered.api.proxy.player.ConnectionRequestBuilder;
 import com.velocitypowered.api.proxy.player.ConnectionRequestBuilder.Status;
 import com.velocitypowered.api.proxy.server.RegisteredServer;
 import com.velocitypowered.proxy.network.packet.clientbound.ClientboundDisconnectPacket;
-import java.util.Optional;
 import javax.annotation.Nullable;
 import net.kyori.adventure.text.Component;
 import net.kyori.adventure.text.serializer.gson.GsonComponentSerializer;
@@ -89,8 +88,8 @@ public class ConnectionRequestResults {
     }
 
     @Override
-    public Optional<Component> failureReason() {
-      return Optional.ofNullable(component);
+    public @Nullable Component failureReason() {
+      return component;
     }
 
     @Override

proxy/src/main/java/com/velocitypowered/proxy/event/VelocityEventManager.java

@@ -290,12 +290,6 @@ public class VelocityEventManager implements EventManager {
     }
   }
 
-  private PluginContainer ensurePlugin(final Object plugin) {
-    requireNonNull(plugin, "plugin");
-    return pluginManager.fromInstance(plugin)
-        .orElseThrow(() -> new IllegalArgumentException("Specified plugin is not loaded"));
-  }
-
   private void register(final List<HandlerRegistration> registrations) {
     lock.writeLock().lock();
     try {
@@ -315,7 +309,7 @@ public class VelocityEventManager implements EventManager {
   @Override
   public void register(final Object plugin, final Object listener) {
     requireNonNull(listener, "listener");
-    final PluginContainer pluginContainer = ensurePlugin(plugin);
+    final PluginContainer pluginContainer = pluginManager.ensurePluginContainer(plugin);
     if (plugin == listener) {
       throw new IllegalArgumentException("The plugin main instance is automatically registered.");
     }
@@ -326,7 +320,7 @@ public class VelocityEventManager implements EventManager {
   @SuppressWarnings("unchecked")
   public <E> void register(final Object plugin, final Class<E> eventClass,
                            final short order, final EventHandler<E> handler) {
-    final PluginContainer pluginContainer = ensurePlugin(plugin);
+    final PluginContainer pluginContainer = pluginManager.ensurePluginContainer(plugin);
     requireNonNull(eventClass, "eventClass");
     requireNonNull(handler, "handler");
 
@@ -360,13 +354,13 @@ public class VelocityEventManager implements EventManager {
 
   @Override
   public void unregisterListeners(final Object plugin) {
-    final PluginContainer pluginContainer = ensurePlugin(plugin);
+    final PluginContainer pluginContainer = pluginManager.ensurePluginContainer(plugin);
     unregisterIf(registration -> registration.plugin == pluginContainer);
   }
 
   @Override
   public void unregisterListener(final Object plugin, final Object handler) {
-    final PluginContainer pluginContainer = ensurePlugin(plugin);
+    final PluginContainer pluginContainer = pluginManager.ensurePluginContainer(plugin);
     requireNonNull(handler, "handler");
     unregisterIf(registration ->
         registration.plugin == pluginContainer && registration.handler == handler);

proxy/src/main/java/com/velocitypowered/proxy/network/ProtocolUtils.java

@@ -355,9 +355,9 @@ public enum ProtocolUtils {
   public static void writeProperties(ByteBuf buf, List<GameProfile.Property> properties) {
     writeVarInt(buf, properties.size());
     for (GameProfile.Property property : properties) {
-      writeString(buf, property.getName());
-      writeString(buf, property.getValue());
-      String signature = property.getSignature();
+      writeString(buf, property.name());
+      writeString(buf, property.value());
+      String signature = property.signature();
       if (signature != null && !signature.isEmpty()) {
         buf.writeBoolean(true);
         writeString(buf, signature);

proxy/src/main/java/com/velocitypowered/proxy/network/ServerChannelInitializer.java

@@ -17,6 +17,7 @@
 
 package com.velocitypowered.proxy.network;
 
+import static com.velocitypowered.proxy.network.HandlerNames.FLOW_HANDLER;
 import static com.velocitypowered.proxy.network.HandlerNames.FRAME_DECODER;
 import static com.velocitypowered.proxy.network.HandlerNames.FRAME_ENCODER;
 import static com.velocitypowered.proxy.network.HandlerNames.LEGACY_PING_DECODER;
@@ -29,6 +30,7 @@ import com.velocitypowered.proxy.VelocityServer;
 import com.velocitypowered.proxy.connection.MinecraftConnection;
 import com.velocitypowered.proxy.connection.client.HandshakeSessionHandler;
 import com.velocitypowered.proxy.network.packet.PacketDirection;
+import com.velocitypowered.proxy.network.pipeline.AutoReadHolderHandler;
 import com.velocitypowered.proxy.network.pipeline.LegacyPingDecoder;
 import com.velocitypowered.proxy.network.pipeline.LegacyPingEncoder;
 import com.velocitypowered.proxy.network.pipeline.MinecraftDecoder;
@@ -61,7 +63,8 @@ public class ServerChannelInitializer extends ChannelInitializer<Channel> {
         .addLast(LEGACY_PING_ENCODER, LegacyPingEncoder.INSTANCE)
         .addLast(FRAME_ENCODER, MinecraftVarintLengthEncoder.INSTANCE)
         .addLast(MINECRAFT_DECODER, new MinecraftDecoder(PacketDirection.SERVERBOUND))
-        .addLast(MINECRAFT_ENCODER, new MinecraftEncoder(PacketDirection.CLIENTBOUND));
+        .addLast(MINECRAFT_ENCODER, new MinecraftEncoder(PacketDirection.CLIENTBOUND))
+        .addLast(FLOW_HANDLER, new AutoReadHolderHandler());
 
     final MinecraftConnection connection = new MinecraftConnection(ch, this.server);
     connection.setSessionHandler(new HandshakeSessionHandler(connection, this.server));

proxy/src/main/java/com/velocitypowered/proxy/network/packet/AbstractKeepAlivePacket.java

@@ -20,7 +20,6 @@ package com.velocitypowered.proxy.network.packet;
 import com.google.common.base.MoreObjects;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.network.ProtocolUtils;
-import io.netty.buffer.ByteBuf;
 import java.util.function.LongFunction;
 
 public abstract class AbstractKeepAlivePacket implements Packet {

proxy/src/main/java/com/velocitypowered/proxy/network/packet/AbstractStatusPingPacket.java

@@ -18,8 +18,6 @@
 package com.velocitypowered.proxy.network.packet;
 
 import com.google.common.base.MoreObjects;
-import com.velocitypowered.api.network.ProtocolVersion;
-import io.netty.buffer.ByteBuf;
 import java.util.function.LongFunction;
 
 public abstract class AbstractStatusPingPacket implements Packet {

proxy/src/main/java/com/velocitypowered/proxy/network/packet/clientbound/ClientboundDisconnectPacket.java

@@ -22,13 +22,10 @@ import com.google.common.base.Preconditions;
 import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.network.ProtocolUtils;
 import com.velocitypowered.proxy.network.packet.Packet;
-import com.velocitypowered.proxy.network.packet.PacketDirection;
 import com.velocitypowered.proxy.network.packet.PacketHandler;
 import com.velocitypowered.proxy.network.packet.PacketReader;
 import com.velocitypowered.proxy.network.packet.PacketWriter;
-import io.netty.buffer.ByteBuf;
 import net.kyori.adventure.text.Component;
-import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class ClientboundDisconnectPacket implements Packet {
   public static final PacketReader<ClientboundDisconnectPacket> DECODER = (buf, version) ->

proxy/src/main/java/com/velocitypowered/proxy/network/packet/clientbound/ClientboundHeaderAndFooterPacket.java

@@ -21,13 +21,10 @@ import static com.velocitypowered.proxy.network.ProtocolUtils.writeString;
 
 import com.google.common.base.MoreObjects;
 import com.google.common.base.Preconditions;
-import com.velocitypowered.api.network.ProtocolVersion;
-import com.velocitypowered.proxy.network.ProtocolUtils;
 import com.velocitypowered.proxy.network.packet.Packet;
 import com.velocitypowered.proxy.network.packet.PacketHandler;
 import com.velocitypowered.proxy.network.packet.PacketReader;
 import com.velocitypowered.proxy.network.packet.PacketWriter;
-import io.netty.buffer.ByteBuf;
 
 public class ClientboundHeaderAndFooterPacket implements Packet {
   public static final PacketReader<ClientboundHeaderAndFooterPacket> DECODER = PacketReader.unsupported();

proxy/src/main/java/com/velocitypowered/proxy/network/packet/clientbound/ClientboundPlayerListItemPacket.java

@@ -205,12 +205,12 @@ public class ClientboundPlayerListItemPacket implements Packet {
     }
 
     public static Item from(TabListEntry entry) {
-      return new Item(entry.gameProfile().getId())
-          .setName(entry.gameProfile().getName())
-          .setProperties(entry.gameProfile().getProperties())
+      return new Item(entry.gameProfile().uuid())
+          .setName(entry.gameProfile().name())
+          .setProperties(entry.gameProfile().properties())
           .setLatency(entry.ping())
           .setGameMode(entry.gameMode())
-          .setDisplayName(entry.displayName().orElse(null));
+          .setDisplayName(entry.displayName());
     }
 
     public @Nullable UUID getUuid() {

proxy/src/main/java/com/velocitypowered/proxy/network/packet/clientbound/ClientboundResourcePackRequestPacket.java

@@ -18,13 +18,11 @@
 package com.velocitypowered.proxy.network.packet.clientbound;
 
 import com.google.common.base.MoreObjects;
-import com.velocitypowered.api.network.ProtocolVersion;
 import com.velocitypowered.proxy.network.ProtocolUtils;
 import com.velocitypowered.proxy.network.packet.Packet;
 import com.velocitypowered.proxy.network.packet.PacketHandler;
 import com.velocitypowered.proxy.network.packet.PacketReader;
 import com.velocitypowered.proxy.network.packet.PacketWriter;
-import io.netty.buffer.ByteBuf;
 import java.util.Objects;
 
 public class ClientboundResourcePackRequestPacket implements Packet {

proxy/src/main/java/com/velocitypowered/proxy/network/packet/clientbound/ClientboundServerLoginSuccessPacket.java

@@ -25,7 +25,6 @@ import com.velocitypowered.proxy.network.packet.Packet;
 import com.velocitypowered.proxy.network.packet.PacketHandler;
 import com.velocitypowered.proxy.network.packet.PacketReader;
 import com.velocitypowered.proxy.network.packet.PacketWriter;
-import io.netty.buffer.ByteBuf;
 import java.util.Objects;
 import java.util.UUID;
 

proxy/src/main/java/com/velocitypowered/proxy/network/packet/legacy/LegacyDisconnectPacket.java

@@ -45,7 +45,10 @@ public class LegacyDisconnectPacket implements LegacyPacket {
    */
   public static LegacyDisconnectPacket fromServerPing(ServerPing response,
                                                       LegacyMinecraftPingVersion version) {
-    Players players = response.players().orElse(FAKE_PLAYERS);
+    Players players = response.players();
+    if (players == null) {
+      players = FAKE_PLAYERS;
+    }
 
     switch (version) {
       case MINECRAFT_1_3:

proxy/src/main/java/com/velocitypowered/proxy/network/packet/serverbound/ServerboundHandshakePacket.java

@@ -24,7 +24,6 @@ import com.velocitypowered.proxy.network.packet.Packet;
 import com.velocitypowered.proxy.network.packet.PacketHandler;
 import com.velocitypowered.proxy.network.packet.PacketReader;
 import com.velocitypowered.proxy.network.packet.PacketWriter;
-import io.netty.buffer.ByteBuf;
 
 public class ServerboundHandshakePacket implements Packet {
   public static final PacketReader<ServerboundHandshakePacket> DECODER = (buf, version) -> {

proxy/src/main/java/com/velocitypowered/proxy/network/pipeline/GS4QueryHandler.java

@@ -43,7 +43,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
-import java.util.Optional;
 import java.util.concurrent.TimeUnit;
 import java.util.stream.Collectors;
 import net.kyori.adventure.text.serializer.plain.PlainComponentSerializer;
@@ -203,8 +202,8 @@ public class GS4QueryHandler extends SimpleChannelInboundHandler<DatagramPacket>
     List<QueryResponse.PluginInformation> result = new ArrayList<>();
     for (PluginContainer plugin : server.pluginManager().plugins()) {
       PluginDescription description = plugin.description();
-      result.add(QueryResponse.PluginInformation.of(description.name()
-          .orElse(description.id()), description.version().orElse(null)));
+      result.add(QueryResponse.PluginInformation.of(description.name(),
+          description.version()));
     }
     return result;
   }
@@ -272,8 +271,10 @@ public class GS4QueryHandler extends SimpleChannelInboundHandler<DatagramPacket>
       while (iterator.hasNext()) {
         QueryResponse.PluginInformation info = iterator.next();
         pluginsString.append(info.getName());
-        Optional<String> version = info.getVersion();
-        version.ifPresent(s -> pluginsString.append(' ').append(s));
+        String version = info.getVersion();
+        if (version != null) {
+          pluginsString.append(' ').append(version);
+        }
         if (iterator.hasNext()) {
           pluginsString.append(';').append(' ');
         }

proxy/src/main/java/com/velocitypowered/proxy/network/pipeline/MinecraftDecoder.java

@@ -73,11 +73,11 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
 
     int originalReaderIndex = buf.readerIndex();
     int packetId = ProtocolUtils.readVarInt(buf);
-    Packet packet = null;
+    Packet packet;
     try {
       packet = this.registry.readPacket(packetId, buf, this.version);
     } catch (Exception e) {
-      throw handleDecodeFailure(e, packet, packetId); // TODO: packet is always null
+      throw handleDecodeFailure(e, packetId);
     }
     if (packet == null) {
       buf.readerIndex(originalReaderIndex);
@@ -85,7 +85,7 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
     } else {
       try {
         if (buf.isReadable()) {
-          throw handleOverflow(packet, buf.readerIndex(), buf.writerIndex());
+          throw handleOverflow(packetId, buf.readerIndex(), buf.writerIndex());
         }
         ctx.fireChannelRead(packet);
       } finally {
@@ -94,39 +94,43 @@ public class MinecraftDecoder extends ChannelInboundHandlerAdapter {
     }
   }
 
-  private void doLengthSanityChecks(ByteBuf buf, Packet packet) throws Exception {
+  // TODO: Reimplement this
+  private void doLengthSanityChecks(ByteBuf buf, int packetId, Packet packet) throws Exception {
     int expectedMinLen = packet.expectedMinLength(buf, direction, version);
     int expectedMaxLen = packet.expectedMaxLength(buf, direction, version);
     if (expectedMaxLen != -1 && buf.readableBytes() > expectedMaxLen) {
-      throw handleOverflow(packet, expectedMaxLen, buf.readableBytes());
+      throw handleOverflow(packetId, expectedMaxLen, buf.readableBytes());
     }
     if (buf.readableBytes() < expectedMinLen) {
-      throw handleUnderflow(packet, expectedMaxLen, buf.readableBytes());
+      throw handleUnderflow(packetId, expectedMaxLen, buf.readableBytes());
     }
   }
 
-  private Exception handleOverflow(Packet packet, int expected, int actual) {
+  private Exception handleOverflow(int packetId, int expected, int actual) {
     if (DEBUG) {
-      return new CorruptedFrameException("Packet sent for " + packet.getClass() + " was too "
+      Class<? extends Packet> packetClass = this.registry.lookupPacket(packetId);
+      return new CorruptedFrameException("Packet sent for " + packetClass + " was too "
           + "big (expected " + expected + " bytes, got " + actual + " bytes)");
     } else {
       return DECODE_FAILED;
     }
   }
 
-  private Exception handleUnderflow(Packet packet, int expected, int actual) {
+  private Exception handleUnderflow(int packetId, int expected, int actual) {
     if (DEBUG) {
-      return new CorruptedFrameException("Packet sent for " + packet.getClass() + " was too "
+      Class<? extends Packet> packetClass = this.registry.lookupPacket(packetId);
+      return new CorruptedFrameException("Packet sent for " + packetClass + " was too "
           + "small (expected " + expected + " bytes, got " + actual + " bytes)");
     } else {
       return DECODE_FAILED;
     }
   }
 
-  private Exception handleDecodeFailure(Exception cause, Packet packet, int packetId) {
+  private Exception handleDecodeFailure(Exception cause, int packetId) {
     if (DEBUG) {
+      Class<? extends Packet> packetClass = this.registry.lookupPacket(packetId);
       return new CorruptedFrameException(
-          "Error decoding " + packet.getClass() + " " + getExtraConnectionDetail(packetId), cause);
+          "Error decoding " + packetClass + " " + getExtraConnectionDetail(packetId), cause);
     } else {
       return DECODE_FAILED;
     }

proxy/src/main/java/com/velocitypowered/proxy/network/registry/packet/DensePacketRegistryMap.java

@@ -36,7 +36,7 @@ public class DensePacketRegistryMap implements PacketRegistryMap {
 
   private final PacketReader<?>[] readersById;
   private final PacketWriter[] writersByClass;
-  private final Class<?>[] classesById;
+  private final Class<?>[] classesByKey;
   private final int[] idsByKey;
 
   public DensePacketRegistryMap(Int2ObjectMap<PacketMapping<?>> mappings) {
@@ -44,7 +44,7 @@ public class DensePacketRegistryMap implements PacketRegistryMap {
 
     this.readersById = new PacketReader[size];
     this.writersByClass = new PacketWriter[size * 2];
-    this.classesById = new Class[size * 2];
+    this.classesByKey = new Class[size * 2];
     this.idsByKey = new int[size * 2];
 
     for (PacketMapping<?> value : mappings.values()) {
@@ -56,41 +56,41 @@ public class DensePacketRegistryMap implements PacketRegistryMap {
   private void place(int packetId, Class<?> key, PacketWriter<?> value) {
     int bucket = findEmpty(key);
     this.writersByClass[bucket] = value;
-    this.classesById[bucket] = key;
+    this.classesByKey[bucket] = key;
     this.idsByKey[bucket] = packetId;
   }
 
   private int findEmpty(Class<?> key) {
-    int start = key.hashCode() % this.classesById.length;
+    int start = key.hashCode() % this.classesByKey.length;
     int index = start;
 
     for (;;) {
-      if (this.classesById[index] == null || this.classesById[index].equals(key)) {
+      if (this.classesByKey[index] == null || this.classesByKey[index].equals(key)) {
         // It's available, so no chance that this value exists anywhere in the map.
         return index;
       }
 
-      if ((index = (index + 1) % this.classesById.length) == start) {
+      if ((index = (index + 1) % this.classesByKey.length) == start) {
         return -1;
       }
     }
   }
 
   private int index(Class<?> key) {
-    int start = key.hashCode() % this.classesById.length;
+    int start = key.hashCode() % this.classesByKey.length;
     int index = start;
 
     for (;;) {
-      if (this.classesById[index] == null) {
+      if (this.classesByKey[index] == null) {
         // It's available, so no chance that this value exists anywhere in the map.
         return -1;
       }
-      if (key.equals(this.classesById[index])) {
+      if (key.equals(this.classesByKey[index])) {
         return index;
       }
 
       // Conflict, keep probing ...
-      if ((index = (index + 1) % this.classesById.length) == start) {
+      if ((index = (index + 1) % this.classesByKey.length) == start) {
         return -1;
       }
     }
@@ -119,4 +119,14 @@ public class DensePacketRegistryMap implements PacketRegistryMap {
     }
 
   }
+
+  @Override
+  public @Nullable Class<? extends Packet> lookupPacket(int id) {
+    for (int bucket = 0; bucket < this.idsByKey.length; bucket++) {
+      if (this.idsByKey[bucket] == id) {
+        return (Class<? extends Packet>) this.classesByKey[bucket];
+      }
+    }
+    return null;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/network/registry/packet/EmptyPacketRegistryMap.java

@@ -42,4 +42,9 @@ public class EmptyPacketRegistryMap implements PacketRegistryMap {
         packet.getClass().getName(), version
     ));
   }
+
+  @Override
+  public @Nullable Class<? extends Packet> lookupPacket(int id) {
+    return null;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/network/registry/packet/PacketRegistryMap.java

@@ -26,4 +26,6 @@ public interface PacketRegistryMap {
   @Nullable Packet readPacket(final int id, ByteBuf buf, ProtocolVersion version);
 
   <P extends Packet> void writePacket(P packet, ByteBuf buf, ProtocolVersion version);
+
+  @Nullable Class<? extends Packet> lookupPacket(final int id);
 }

proxy/src/main/java/com/velocitypowered/proxy/network/registry/packet/RegularPacketRegistryMap.java

@@ -27,6 +27,7 @@ import io.netty.buffer.ByteBuf;
 import it.unimi.dsi.fastutil.ints.Int2ObjectMap;
 import it.unimi.dsi.fastutil.ints.Int2ObjectOpenHashMap;
 import it.unimi.dsi.fastutil.objects.Object2IntMap;
+import it.unimi.dsi.fastutil.objects.Object2IntMap.Entry;
 import it.unimi.dsi.fastutil.objects.Object2IntOpenHashMap;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -81,4 +82,14 @@ public class RegularPacketRegistryMap implements PacketRegistryMap {
     ProtocolUtils.writeVarInt(buf, packetId);
     writer.write(buf, packet, version);
   }
+
+  @Override
+  public @Nullable Class<? extends Packet> lookupPacket(int id) {
+    for (Entry<Class<?>> entry : this.classesById.object2IntEntrySet()) {
+      if (entry.getIntValue() == id) {
+        return (Class<? extends Packet>) entry.getKey();
+      }
+    }
+    return null;
+  }
 }

proxy/src/main/java/com/velocitypowered/proxy/network/registry/state/PlayPacketRegistry.java

@@ -462,6 +462,17 @@ class PlayPacketRegistry implements ProtocolRegistry {
         //noinspection unchecked
         encoder.write(buf, packet, version);
       }
+
+      @Override
+      public @Nullable Class<? extends Packet> lookupPacket(int id) {
+        for (Object2IntMap.Entry<Class<? extends Packet>> entry : this.packetClassToId
+            .object2IntEntrySet()) {
+          if (entry.getIntValue() == id) {
+            return entry.getKey();
+          }
+        }
+        return null;
+      }
     }
   }
 

proxy/src/main/java/com/velocitypowered/proxy/network/serialization/GameProfileSerializer.java

@@ -51,9 +51,9 @@ public final class GameProfileSerializer implements JsonSerializer<GameProfile>,
   @Override
   public JsonElement serialize(GameProfile src, Type typeOfSrc, JsonSerializationContext context) {
     JsonObject obj = new JsonObject();
-    obj.add("id", new JsonPrimitive(src.getUndashedId()));
-    obj.add("name", new JsonPrimitive(src.getName()));
-    obj.add("properties", context.serialize(src.getProperties(), propertyList));
+    obj.add("id", new JsonPrimitive(src.undashedId()));
+    obj.add("name", new JsonPrimitive(src.name()));
+    obj.add("properties", context.serialize(src.properties(), propertyList));
     return obj;
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/plugin/VelocityPluginManager.java

@@ -21,6 +21,7 @@ import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
 import com.google.common.base.Joiner;
+import com.google.common.base.MoreObjects;
 import com.google.inject.AbstractModule;
 import com.google.inject.Module;
 import com.google.inject.name.Names;
@@ -52,6 +53,7 @@ import java.util.Optional;
 import java.util.Set;
 import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class VelocityPluginManager implements PluginManager {
 
@@ -110,9 +112,9 @@ public class VelocityPluginManager implements PluginManager {
     for (PluginDescription candidate : sortedPlugins) {
       // Verify dependencies
       for (PluginDependency dependency : candidate.dependencies()) {
-        if (!dependency.isOptional() && !loadedPluginsById.contains(dependency.getId())) {
+        if (!dependency.optional() && !loadedPluginsById.contains(dependency.id())) {
           logger.error("Can't load plugin {} due to missing dependency {}", candidate.id(),
-              dependency.getId());
+              dependency.id());
           continue pluginLoad;
         }
       }
@@ -154,27 +156,27 @@ public class VelocityPluginManager implements PluginManager {
         continue;
       }
 
-      logger.info("Loaded plugin {} {} by {}", description.id(), description.version()
-          .orElse("<UNKNOWN>"), Joiner.on(", ").join(description.authors()));
+      logger.info("Loaded plugin {} {} by {}", description.id(), MoreObjects.firstNonNull(
+          description.version(), "<UNKNOWN>"), Joiner.on(", ").join(description.authors()));
       registerPlugin(container);
     }
   }
 
   @Override
-  public Optional<PluginContainer> fromInstance(Object instance) {
+  public @Nullable PluginContainer fromInstance(Object instance) {
     checkNotNull(instance, "instance");
 
     if (instance instanceof PluginContainer) {
-      return Optional.of((PluginContainer) instance);
+      return (PluginContainer) instance;
     }
 
-    return Optional.ofNullable(pluginInstances.get(instance));
+    return pluginInstances.get(instance);
   }
 
   @Override
-  public Optional<PluginContainer> getPlugin(String id) {
+  public @Nullable PluginContainer getPlugin(String id) {
     checkNotNull(id, "id");
-    return Optional.ofNullable(plugins.get(id));
+    return plugins.get(id);
   }
 
   @Override
@@ -191,9 +193,12 @@ public class VelocityPluginManager implements PluginManager {
   public void addToClasspath(Object plugin, Path path) {
     checkNotNull(plugin, "instance");
     checkNotNull(path, "path");
-    Optional<PluginContainer> optContainer = fromInstance(plugin);
-    checkArgument(optContainer.isPresent(), "plugin is not loaded");
-    Optional<?> optInstance = optContainer.get().instance();
+    PluginContainer optContainer = fromInstance(plugin);
+    if (optContainer == null) {
+      throw new IllegalArgumentException("plugin is not loaded");
+    }
+
+    Optional<?> optInstance = optContainer.instance();
     checkArgument(optInstance.isPresent(), "plugin has no instance");
 
     ClassLoader pluginClassloader = optInstance.get().getClass().getClassLoader();

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/VelocityPluginDescription.java

@@ -28,7 +28,6 @@ import java.nio.file.Path;
 import java.util.Collection;
 import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class VelocityPluginDescription implements PluginDescription {
@@ -62,7 +61,7 @@ public class VelocityPluginDescription implements PluginDescription {
     this.description = Strings.emptyToNull(description);
     this.url = Strings.emptyToNull(url);
     this.authors = authors == null ? ImmutableList.of() : ImmutableList.copyOf(authors);
-    this.dependencies = Maps.uniqueIndex(dependencies, d -> d == null ? null : d.getId());
+    this.dependencies = Maps.uniqueIndex(dependencies, d -> d == null ? null : d.id());
     this.source = source;
   }
 
@@ -72,23 +71,23 @@ public class VelocityPluginDescription implements PluginDescription {
   }
 
   @Override
-  public Optional<String> name() {
-    return Optional.ofNullable(name);
+  public String name() {
+    return name == null ? id : name;
   }
 
   @Override
-  public Optional<String> version() {
-    return Optional.ofNullable(version);
+  public @Nullable String version() {
+    return version;
   }
 
   @Override
-  public Optional<String> description() {
-    return Optional.ofNullable(description);
+  public @Nullable String description() {
+    return description;
   }
 
   @Override
-  public Optional<String> url() {
-    return Optional.ofNullable(url);
+  public @Nullable String url() {
+    return url;
   }
 
   @Override
@@ -102,13 +101,13 @@ public class VelocityPluginDescription implements PluginDescription {
   }
 
   @Override
-  public Optional<PluginDependency> getDependency(String id) {
-    return Optional.ofNullable(dependencies.get(id));
+  public @Nullable PluginDependency getDependency(String id) {
+    return dependencies.get(id);
   }
 
   @Override
-  public Optional<Path> file() {
-    return Optional.ofNullable(source);
+  public @Nullable Path file() {
+    return source;
   }
 
   @Override

proxy/src/main/java/com/velocitypowered/proxy/plugin/loader/java/JavaPluginLoader.java

@@ -78,7 +78,10 @@ public class JavaPluginLoader implements PluginLoader {
       throw new IllegalArgumentException("Description provided isn't of the Java plugin loader");
     }
 
-    URL pluginJarUrl = source.file().get().toUri().toURL();
+    Path jarFilePath = source.file();
+    assert jarFilePath != null;
+
+    URL pluginJarUrl = jarFilePath.toUri().toURL();
     PluginClassLoader loader = AccessController.doPrivileged(
         (PrivilegedAction<PluginClassLoader>) () -> new PluginClassLoader(new URL[]{pluginJarUrl}));
     loader.addToClassloaders();
@@ -97,9 +100,9 @@ public class JavaPluginLoader implements PluginLoader {
     }
 
     JavaVelocityPluginDescription javaDescription = (JavaVelocityPluginDescription) description;
-    Optional<Path> source = javaDescription.file();
+    Path source = javaDescription.file();
 
-    if (!source.isPresent()) {
+    if (source == null) {
       throw new IllegalArgumentException("No path in plugin description");
     }
 
@@ -184,13 +187,13 @@ public class JavaPluginLoader implements PluginLoader {
       Class mainClass) {
     return new JavaVelocityPluginDescription(
         description.id(),
-        description.name().orElse(null),
-        description.version().orElse(null),
-        description.description().orElse(null),
-        description.url().orElse(null),
+        description.name(),
+        description.version(),
+        description.description(),
+        description.url(),
         description.authors(),
         description.dependencies(),
-        description.file().orElse(null),
+        description.file(),
         mainClass
     );
   }

proxy/src/main/java/com/velocitypowered/proxy/plugin/util/PluginDependencyUtils.java

@@ -63,7 +63,7 @@ public class PluginDependencyUtils {
       graph.addNode(description);
 
       for (PluginDependency dependency : description.dependencies()) {
-        PluginDescription in = candidateMap.get(dependency.getId());
+        PluginDescription in = candidateMap.get(dependency.id());
 
         if (in != null) {
           graph.putEdge(description, in);

proxy/src/main/java/com/velocitypowered/proxy/scheduler/VelocityScheduler.java

@@ -24,6 +24,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
 import com.google.common.util.concurrent.ThreadFactoryBuilder;
+import com.velocitypowered.api.plugin.PluginDescription;
 import com.velocitypowered.api.plugin.PluginManager;
 import com.velocitypowered.api.scheduler.ScheduledTask;
 import com.velocitypowered.api.scheduler.Scheduler;
@@ -66,7 +67,7 @@ public class VelocityScheduler implements Scheduler {
   public TaskBuilder buildTask(Object plugin, Runnable runnable) {
     checkNotNull(plugin, "plugin");
     checkNotNull(runnable, "runnable");
-    checkArgument(pluginManager.fromInstance(plugin).isPresent(), "plugin is not registered");
+    checkArgument(pluginManager.fromInstance(plugin) != null, "plugin is not registered");
     return new TaskBuilderImpl(plugin, runnable);
   }
 
@@ -205,12 +206,10 @@ public class VelocityScheduler implements Scheduler {
           if (e instanceof InterruptedException) {
             Thread.currentThread().interrupt();
           } else {
-            String friendlyPluginName = pluginManager.fromInstance(plugin)
-                .map(container -> container.description().name()
-                      .orElse(container.description().id()))
-                .orElse("UNKNOWN");
-            Log.logger.error("Exception in task {} by plugin {}", runnable, friendlyPluginName,
-                e);
+            PluginDescription description = pluginManager.ensurePluginContainer(plugin)
+                .description();
+            Log.logger.error("Exception in task {} by plugin {}", runnable,
+                description.name(), e);
           }
         } finally {
           if (repeat == 0) {

proxy/src/main/java/com/velocitypowered/proxy/server/ServerMap.java

@@ -25,7 +25,6 @@ import com.velocitypowered.proxy.VelocityServer;
 import java.util.Collection;
 import java.util.Locale;
 import java.util.Map;
-import java.util.Optional;
 import java.util.concurrent.ConcurrentHashMap;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -44,10 +43,10 @@ public class ServerMap {
    * @param name the name to look up
    * @return the server, if it exists
    */
-  public Optional<RegisteredServer> getServer(String name) {
+  public @Nullable RegisteredServer getServer(String name) {
     Preconditions.checkNotNull(name, "server");
     String lowerName = name.toLowerCase(Locale.US);
-    return Optional.ofNullable(servers.get(lowerName));
+    return servers.get(lowerName);
   }
 
   public Collection<RegisteredServer> getAllServers() {

proxy/src/main/java/com/velocitypowered/proxy/tablist/VelocityTabList.java

@@ -31,7 +31,6 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
-import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
 import net.kyori.adventure.text.Component;
@@ -75,18 +74,18 @@ public class VelocityTabList implements TabList {
     Preconditions.checkNotNull(entry, "entry");
     Preconditions.checkArgument(entry.parent().equals(this),
         "The provided entry was not created by this tab list");
-    Preconditions.checkArgument(!entries.containsKey(entry.gameProfile().getId()),
+    Preconditions.checkArgument(!entries.containsKey(entry.gameProfile().uuid()),
         "this TabList already contains an entry with the same uuid");
     Preconditions.checkArgument(entry instanceof VelocityTabListEntry,
         "Not a Velocity tab list entry");
 
     connection.write(new ClientboundPlayerListItemPacket(ClientboundPlayerListItemPacket.ADD_PLAYER,
         Collections.singletonList(ClientboundPlayerListItemPacket.Item.from(entry))));
-    entries.put(entry.gameProfile().getId(), (VelocityTabListEntry) entry);
+    entries.put(entry.gameProfile().uuid(), (VelocityTabListEntry) entry);
   }
 
   @Override
-  public Optional<TabListEntry> removeEntry(UUID uuid) {
+  public @Nullable TabListEntry removeEntry(UUID uuid) {
     Preconditions.checkNotNull(uuid, "uuid");
 
     TabListEntry entry = entries.remove(uuid);
@@ -97,7 +96,7 @@ public class VelocityTabList implements TabList {
       ));
     }
 
-    return Optional.ofNullable(entry);
+    return entry;
   }
 
   @Override
@@ -202,7 +201,7 @@ public class VelocityTabList implements TabList {
   }
 
   void updateEntry(int action, TabListEntry entry) {
-    if (entries.containsKey(entry.gameProfile().getId())) {
+    if (entries.containsKey(entry.gameProfile().uuid())) {
       connection.write(new ClientboundPlayerListItemPacket(action,
           Collections.singletonList(ClientboundPlayerListItemPacket.Item.from(entry))));
     }

proxy/src/main/java/com/velocitypowered/proxy/tablist/VelocityTabListEntry.java

@@ -21,7 +21,6 @@ import com.velocitypowered.api.proxy.player.TabList;
 import com.velocitypowered.api.proxy.player.TabListEntry;
 import com.velocitypowered.api.util.GameProfile;
 import com.velocitypowered.proxy.network.packet.clientbound.ClientboundPlayerListItemPacket;
-import java.util.Optional;
 import net.kyori.adventure.text.Component;
 import org.checkerframework.checker.nullness.qual.Nullable;
 
@@ -53,8 +52,8 @@ public class VelocityTabListEntry implements TabListEntry {
   }
 
   @Override
-  public Optional<Component> displayName() {
-    return Optional.ofNullable(displayName);
+  public @Nullable Component displayName() {
+    return displayName;
   }
 
   @Override

proxy/src/main/java/com/velocitypowered/proxy/tablist/VelocityTabListEntryLegacy.java

@@ -31,7 +31,7 @@ public class VelocityTabListEntryLegacy extends VelocityTabListEntry {
 
   @Override
   public TabListEntry setDisplayName(@Nullable Component displayName) {
-    parent().removeEntry(gameProfile().getId()); // We have to remove first if updating
+    parent().removeEntry(gameProfile().uuid()); // We have to remove first if updating
     return super.setDisplayName(displayName);
   }
 }

proxy/src/main/java/com/velocitypowered/proxy/tablist/VelocityTabListLegacy.java

@@ -25,7 +25,6 @@ import com.velocitypowered.proxy.network.packet.clientbound.ClientboundPlayerLis
 import com.velocitypowered.proxy.network.packet.clientbound.ClientboundPlayerListItemPacket.Item;
 import java.util.Collections;
 import java.util.Map;
-import java.util.Optional;
 import java.util.UUID;
 import java.util.concurrent.ConcurrentHashMap;
 import net.kyori.adventure.text.Component;
@@ -50,13 +49,15 @@ public class VelocityTabListLegacy extends VelocityTabList {
   @Override
   public void addEntry(TabListEntry entry) {
     super.addEntry(entry);
-    nameMapping.put(entry.gameProfile().getName(), entry.gameProfile().getId());
+    nameMapping.put(entry.gameProfile().name(), entry.gameProfile().uuid());
   }
 
   @Override
-  public Optional<TabListEntry> removeEntry(UUID uuid) {
-    Optional<TabListEntry> entry = super.removeEntry(uuid);
-    entry.map(TabListEntry::gameProfile).map(GameProfile::getName).ifPresent(nameMapping::remove);
+  public @Nullable TabListEntry removeEntry(UUID uuid) {
+    TabListEntry entry = super.removeEntry(uuid);
+    if (entry != null) {
+      nameMapping.remove(entry.gameProfile().name());
+    }
     return entry;
   }
 
@@ -108,7 +109,7 @@ public class VelocityTabListLegacy extends VelocityTabList {
 
   @Override
   void updateEntry(int action, TabListEntry entry) {
-    if (entries.containsKey(entry.gameProfile().getId())) {
+    if (entries.containsKey(entry.gameProfile().uuid())) {
       switch (action) {
         case ClientboundPlayerListItemPacket.UPDATE_LATENCY:
         case ClientboundPlayerListItemPacket.UPDATE_DISPLAY_NAME: // Add here because we

proxy/src/main/java/com/velocitypowered/proxy/util/InformationUtils.java

@@ -59,11 +59,11 @@ public enum InformationUtils {
       PluginDescription desc = plugin.description();
       JsonObject current = new JsonObject();
       current.addProperty("id", desc.id());
-      if (desc.name().isPresent()) {
-        current.addProperty("name", desc.name().get());
-      }
-      if (desc.version().isPresent()) {
-        current.addProperty("version", desc.version().get());
+      current.addProperty("name", desc.name());
+
+      String version = desc.version();
+      if (version != null) {
+        current.addProperty("version", version);
       }
       if (!desc.authors().isEmpty()) {
         JsonArray authorsArray = new JsonArray();
@@ -72,16 +72,19 @@ public enum InformationUtils {
         }
         current.add("authors", authorsArray);
       }
-      if (desc.description().isPresent()) {
-        current.addProperty("description", desc.description().get());
+
+      String humanDesc = desc.description();
+      if (humanDesc != null) {
+        current.addProperty("description", humanDesc);
       }
-      if (desc.url().isPresent()) {
-        current.addProperty("url", desc.url().get());
+      String url = desc.url();
+      if (url != null) {
+        current.addProperty("url", url);
       }
       if (!desc.dependencies().isEmpty()) {
         JsonArray dependencies = new JsonArray();
         for (PluginDependency dependency : desc.dependencies()) {
-          dependencies.add(dependency.getId());
+          dependencies.add(dependency.id());
         }
         current.add("dependencies", dependencies);
       }

proxy/src/main/java/com/velocitypowered/proxy/util/bossbar/AdventureBossBarManager.java

@@ -19,7 +19,6 @@ package com.velocitypowered.proxy.util.bossbar;
 
 import com.google.common.collect.MapMaker;
 import com.velocitypowered.api.network.ProtocolVersion;
-import com.velocitypowered.api.proxy.connection.Player;
 import com.velocitypowered.proxy.connection.client.ConnectedPlayer;
 import com.velocitypowered.proxy.network.ProtocolUtils;
 import com.velocitypowered.proxy.network.packet.clientbound.ClientboundBossBarPacket;

proxy/src/test/java/com/velocitypowered/proxy/plugin/MockPluginManager.java

@@ -22,20 +22,20 @@ import com.velocitypowered.api.plugin.PluginContainer;
 import com.velocitypowered.api.plugin.PluginManager;
 import java.nio.file.Path;
 import java.util.Collection;
-import java.util.Optional;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class MockPluginManager implements PluginManager {
 
   public static final PluginManager INSTANCE = new MockPluginManager();
 
   @Override
-  public Optional<PluginContainer> fromInstance(final Object instance) {
-    return Optional.empty();
+  public @Nullable PluginContainer fromInstance(final Object instance) {
+    return null;
   }
 
   @Override
-  public Optional<PluginContainer> getPlugin(final String id) {
-    return Optional.empty();
+  public @Nullable PluginContainer getPlugin(final String id) {
+    return null;
   }
 
   @Override

proxy/src/test/java/com/velocitypowered/proxy/testutil/FakePluginManager.java

@@ -25,6 +25,7 @@ import java.nio.file.Path;
 import java.util.Collection;
 import java.util.Optional;
 import org.checkerframework.checker.nullness.qual.NonNull;
+import org.checkerframework.checker.nullness.qual.Nullable;
 
 public class FakePluginManager implements PluginManager {
 
@@ -35,25 +36,25 @@ public class FakePluginManager implements PluginManager {
   private static final PluginContainer PC_B = new FakePluginContainer("b", PLUGIN_B);
 
   @Override
-  public @NonNull Optional<PluginContainer> fromInstance(@NonNull Object instance) {
+  public @Nullable PluginContainer fromInstance(@NonNull Object instance) {
     if (instance == PLUGIN_A) {
-      return Optional.of(PC_A);
+      return PC_A;
     } else if (instance == PLUGIN_B) {
-      return Optional.of(PC_B);
+      return PC_B;
     } else {
-      return Optional.empty();
+      return null;
     }
   }
 
   @Override
-  public @NonNull Optional<PluginContainer> getPlugin(@NonNull String id) {
+  public @Nullable PluginContainer getPlugin(@NonNull String id) {
     switch (id) {
       case "a":
-        return Optional.of(PC_A);
+        return PC_A;
       case "b":
-        return Optional.of(PC_B);
+        return PC_B;
       default:
-        return Optional.empty();
+        return null;
     }
   }
 

proxy/src/test/java/com/velocitypowered/proxy/util/ServerMapTest.java

@@ -25,7 +25,6 @@ import com.velocitypowered.api.proxy.server.ServerInfo;
 import com.velocitypowered.proxy.server.ServerMap;
 import java.net.InetAddress;
 import java.net.InetSocketAddress;
-import java.util.Optional;
 import org.junit.jupiter.api.Test;
 
 class ServerMapTest {
@@ -39,9 +38,9 @@ class ServerMapTest {
     ServerInfo info = new ServerInfo("TestServer", TEST_ADDRESS);
     RegisteredServer connection = map.register(info);
 
-    assertEquals(Optional.of(connection), map.getServer("TestServer"));
-    assertEquals(Optional.of(connection), map.getServer("testserver"));
-    assertEquals(Optional.of(connection), map.getServer("TESTSERVER"));
+    assertEquals(connection, map.getServer("TestServer"));
+    assertEquals(connection, map.getServer("testserver"));
+    assertEquals(connection, map.getServer("TESTSERVER"));
   }
 
   @Test