Use Optionals for nullable values

bukkit/src/main/java/com/github/games647/fastlogin/bukkit/FastLoginBukkit.java

@@ -2,8 +2,8 @@ package com.github.games647.fastlogin.bukkit;
 
 import com.github.games647.fastlogin.bukkit.commands.CrackedCommand;
 import com.github.games647.fastlogin.bukkit.commands.PremiumCommand;
-import com.github.games647.fastlogin.bukkit.listener.BukkitJoinListener;
-import com.github.games647.fastlogin.bukkit.listener.BungeeCordListener;
+import com.github.games647.fastlogin.bukkit.listener.JoinListener;
+import com.github.games647.fastlogin.bukkit.listener.BungeeListener;
 import com.github.games647.fastlogin.bukkit.listener.protocollib.LoginSkinApplyListener;
 import com.github.games647.fastlogin.bukkit.listener.protocollib.ProtocolLibListener;
 import com.github.games647.fastlogin.bukkit.listener.protocolsupport.ProtocolSupportListener;
@@ -66,7 +66,7 @@ public class FastLoginBukkit extends JavaPlugin implements PlatformPlugin<Comman
             setServerStarted();
 
             //check for incoming messages from the bungeecord version of this plugin
-            getServer().getMessenger().registerIncomingPluginChannel(this, getName(), new BungeeCordListener(this));
+            getServer().getMessenger().registerIncomingPluginChannel(this, getName(), new BungeeListener(this));
             getServer().getMessenger().registerOutgoingPluginChannel(this, getName());
             //register listeners on success
         } else {
@@ -93,7 +93,7 @@ public class FastLoginBukkit extends JavaPlugin implements PlatformPlugin<Comman
         //delay dependency setup because we load the plugin very early where plugins are initialized yet
         getServer().getScheduler().runTaskLater(this, new DelayedAuthHook(this), 5L);
 
-        getServer().getPluginManager().registerEvents(new BukkitJoinListener(this), this);
+        getServer().getPluginManager().registerEvents(new JoinListener(this), this);
 
         //register commands using a unique name
         getCommand("premium").setExecutor(new PremiumCommand(this));
@@ -122,8 +122,8 @@ public class FastLoginBukkit extends JavaPlugin implements PlatformPlugin<Comman
     }
 
     public void sendBungeeActivateMessage(CommandSender sender, String target, boolean activate) {
-        if (sender instanceof Player) {
-            notifyBungeeCord((Player) sender, target, activate, true);
+        if (sender instanceof PluginMessageRecipient) {
+            notifyBungeeCord((PluginMessageRecipient) sender, target, activate, true);
         } else {
             Player firstPlayer = Iterables.getFirst(getServer().getOnlinePlayers(), null);
             if (firstPlayer == null) {

bukkit/src/main/java/com/github/games647/fastlogin/bukkit/hooks/CrazyLoginHook.java

@@ -8,6 +8,7 @@ import de.st_ddt.crazylogin.databases.CrazyLoginDataDatabase;
 import de.st_ddt.crazylogin.listener.PlayerListener;
 import de.st_ddt.crazylogin.metadata.Authenticated;
 
+import java.util.Optional;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.Future;
 import java.util.logging.Level;
@@ -31,7 +32,7 @@ public class CrazyLoginHook implements AuthPlugin<Player> {
     @Override
     public boolean forceLogin(Player player) {
         //not thread-safe operation
-        Future<LoginPlayerData> future = Bukkit.getScheduler().callSyncMethod(crazyLoginPlugin, () -> {
+        Future<Optional<LoginPlayerData>> future = Bukkit.getScheduler().callSyncMethod(crazyLoginPlugin, () -> {
             LoginPlayerData playerData = crazyLoginPlugin.getPlayerData(player);
             if (playerData != null) {
                 //mark the account as logged in
@@ -56,17 +57,17 @@ public class CrazyLoginHook implements AuthPlugin<Player> {
                 playerData.addIP(ip);
                 player.setMetadata("Authenticated", new Authenticated(crazyLoginPlugin, player));
                 crazyLoginPlugin.unregisterDynamicHooks();
-                return playerData;
+                return Optional.of(playerData);
             }
 
-            return null;
+            return Optional.empty();
         });
 
         try {
-            LoginPlayerData result = future.get();
-            if (result != null && result.isLoggedIn()) {
+            Optional<LoginPlayerData> result = future.get().filter(LoginPlayerData::isLoggedIn);
+            if (result.isPresent()) {
                 //SQL-Queries should run async
-                crazyLoginPlugin.getCrazyDatabase().saveWithoutPassword(result);
+                crazyLoginPlugin.getCrazyDatabase().saveWithoutPassword(result.get());
                 return true;
             }
         } catch (InterruptedException | ExecutionException ex) {

bukkit/src/main/java/com/github/games647/fastlogin/bukkit/listener/BungeeListener.java

@@ -27,7 +27,7 @@ import org.bukkit.plugin.messaging.PluginMessageListener;
  * This class also receives the plugin message from the bungeecord version of this plugin in order to get notified if
  * the connection is in online mode.
  */
-public class BungeeCordListener implements PluginMessageListener {
+public class BungeeListener implements PluginMessageListener {
 
     private static final String FILE_NAME = "proxy-whitelist.txt";
 
@@ -35,7 +35,7 @@ public class BungeeCordListener implements PluginMessageListener {
     //null if whitelist is empty so bungeecord support is disabled
     private final Set<UUID> proxyIds;
 
-    public BungeeCordListener(FastLoginBukkit plugin) {
+    public BungeeListener(FastLoginBukkit plugin) {
         this.plugin = plugin;
         this.proxyIds = loadBungeeCordIds();
     }
@@ -70,15 +70,15 @@ public class BungeeCordListener implements PluginMessageListener {
         }
     }
 
-    private void readMessage(Player checkedPlayer, String subchannel, String playerName, Player player) {
+    private void readMessage(Player checkedPlayer, String subChannel, String playerName, Player player) {
         InetSocketAddress address = checkedPlayer.getAddress();
         String id = '/' + address.getAddress().getHostAddress() + ':' + address.getPort();
-        if ("AUTO_LOGIN".equalsIgnoreCase(subchannel)) {
+        if ("AUTO_LOGIN".equalsIgnoreCase(subChannel)) {
             BukkitLoginSession playerSession = new BukkitLoginSession(playerName, true);
             playerSession.setVerified(true);
             plugin.getLoginSessions().put(id, playerSession);
             Bukkit.getScheduler().runTaskAsynchronously(plugin, new ForceLoginTask(plugin.getCore(), player));
-        } else if ("AUTO_REGISTER".equalsIgnoreCase(subchannel)) {
+        } else if ("AUTO_REGISTER".equalsIgnoreCase(subChannel)) {
             Bukkit.getScheduler().runTaskAsynchronously(plugin, () -> {
                 AuthPlugin<Player> authPlugin = plugin.getCore().getAuthPluginHook();
                 try {

bukkit/src/main/java/com/github/games647/fastlogin/bukkit/listener/JoinListener.java

@@ -17,13 +17,13 @@ import org.bukkit.event.player.PlayerQuitEvent;
  * This listener tells authentication plugins if the player has a premium account and we checked it successfully. So the
  * plugin can skip authentication.
  */
-public class BukkitJoinListener implements Listener {
+public class JoinListener implements Listener {
 
     private static final long DELAY_LOGIN = 20L / 2;
 
     private final FastLoginBukkit plugin;
 
-    public BukkitJoinListener(FastLoginBukkit plugin) {
+    public JoinListener(FastLoginBukkit plugin) {
         this.plugin = plugin;
     }
 

bukkit/src/main/java/com/github/games647/fastlogin/bukkit/tasks/ForceLoginTask.java

@@ -53,7 +53,7 @@ public class ForceLoginTask extends ForceLoginManagement<Player, CommandSender,
     @Override
     public boolean isOnline(Player player) {
         try {
-            //the playerlist isn't thread-safe
+            //the player-list isn't thread-safe
             return Bukkit.getScheduler().callSyncMethod(core.getPlugin(), player::isOnline).get();
         } catch (InterruptedException | ExecutionException ex) {
             core.getPlugin().getLogger().log(Level.SEVERE, "Failed to perform thread-safe online check", ex);