level command and refactoring to save and load player

src/main/java/me/unurled/sacredrealms/sr/commands/CommandManager.java

@@ -6,6 +6,7 @@ import java.lang.reflect.InvocationTargetException;
 import me.unurled.sacredrealms.sr.SR;
 import me.unurled.sacredrealms.sr.commands.admin.AttributeCommand;
 import me.unurled.sacredrealms.sr.commands.admin.ClientBuildCommand;
+import me.unurled.sacredrealms.sr.commands.admin.LevelCommand;
 import me.unurled.sacredrealms.sr.commands.player.ResetAdventureCommand;
 import me.unurled.sacredrealms.sr.managers.Manager;
 import org.bukkit.command.PluginCommand;
@@ -36,6 +37,7 @@ public class CommandManager extends Manager {
 
     registerCommand("attributes", AttributeCommand.class);
     registerCommand("clientbuild", ClientBuildCommand.class);
+    registerCommand("level", LevelCommand.class);
 
     registerCommand("resetadventure", ResetAdventureCommand.class);
   }

src/main/java/me/unurled/sacredrealms/sr/commands/admin/AttributeCommand.java

@@ -182,6 +182,8 @@ public class AttributeCommand implements TabExecutor {
             "Set " + attribute.getName() + " to " + value + " for " + target.getName());
         player.setItemAttributes(attribute, target.getInventory().getItemInMainHand(), value);
         syncSRToPlayer(player, target);
+        PlayerManager pm = PlayerManager.getInstance(PlayerManager.class);
+        pm.savePlayer(player);
       } catch (NumberFormatException e) {
         sender.sendMessage("Invalid value.");
       }
@@ -202,6 +204,8 @@ public class AttributeCommand implements TabExecutor {
       player.removeItemAttributes(attribute, target.getInventory().getItemInMainHand());
       syncSRToPlayer(player, target);
       sender.sendMessage("Removed " + attribute.getName() + " for " + target.getName());
+      PlayerManager pm = PlayerManager.getInstance(PlayerManager.class);
+      pm.savePlayer(player);
     } else {
       sender.sendMessage("Usage: /attribute <set|get|remove> <player> <attribute> [value]");
     }

src/main/java/me/unurled/sacredrealms/sr/commands/admin/LevelCommand.java

@@ -0,0 +1,82 @@
+package me.unurled.sacredrealms.sr.commands.admin;
+
+import java.util.List;
+import me.unurled.sacredrealms.sr.components.player.PlayerManager;
+import me.unurled.sacredrealms.sr.components.player.SRPlayer;
+import org.bukkit.command.Command;
+import org.bukkit.command.CommandSender;
+import org.bukkit.command.TabExecutor;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
+
+public class LevelCommand implements TabExecutor {
+
+  /**
+   * Executes the given command, returning its success. <br>
+   * If false is returned, then the "usage" plugin.yml entry for this command (if defined) will be
+   * sent to the player.
+   *
+   * @param sender Source of the command
+   * @param command Command which was executed
+   * @param label Alias of the command which was used
+   * @param args Passed command arguments
+   * @return true if a valid command, otherwise false
+   */
+  @Override
+  public boolean onCommand(
+      @NotNull CommandSender sender,
+      @NotNull Command command,
+      @NotNull String label,
+      @NotNull String[] args) {
+    if (!sender.hasPermission("sr.level")) {
+      sender.sendMessage("You do not have permission to use this command.");
+      return true;
+    }
+
+    if (args.length != 2) {
+      sender.sendMessage("Usage: /level <player> <level>");
+      return true;
+    }
+
+    Player target = sender.getServer().getPlayer(args[0]);
+
+    if (target == null) {
+      sender.sendMessage("Player not found.");
+      return true;
+    }
+
+    PlayerManager pm = PlayerManager.getInstance(PlayerManager.class);
+    SRPlayer player = pm.getPlayer(target.getUniqueId());
+
+    if (player != null) {
+      player.setLevel(Integer.parseInt(args[1]));
+      // save player data
+      pm.savePlayer(player);
+    } else {
+      sender.sendMessage("Player not found.");
+    }
+    return true;
+  }
+
+  /**
+   * Requests a list of possible completions for a command argument.
+   *
+   * @param sender Source of the command. For players tab-completing a command inside of a command
+   *     block, this will be the player, not the command block.
+   * @param command Command which was executed
+   * @param label Alias of the command which was used
+   * @param args The arguments passed to the command, including final partial argument to be
+   *     completed
+   * @return A List of possible completions for the final argument, or null to default to the
+   *     command executor
+   */
+  @Override
+  public @Nullable List<String> onTabComplete(
+      @NotNull CommandSender sender,
+      @NotNull Command command,
+      @NotNull String label,
+      @NotNull String[] args) {
+    return null;
+  }
+}

src/main/java/me/unurled/sacredrealms/sr/components/player/PlayerManager.java

@@ -30,6 +30,7 @@ public class PlayerManager extends Manager {
 
   public static final String PLAYER_KEY = "sr.players.";
   private final HashMap<UUID, SRPlayer> players;
+  private DataHandler dh;
 
   public PlayerManager() {
     super();
@@ -39,21 +40,18 @@ public class PlayerManager extends Manager {
   /** Save the data */
   @Override
   public void saveData() {
-    DataManager dm = DataManager.getInstance(DataManager.class);
-    if (dm == null) {
-      error("DataManager is null, Can't save player data.");
-      return;
+    if (dh == null) {
+      DataManager dm = DataManager.getInstance(DataManager.class);
+      if (dm == null) {
+        error("DataManager is null, Can't save player data.");
+        return;
+      }
+      dh = dm.getDataHandler();
     }
-    DataHandler dh = dm.getDataHandler();
+
     // save all players
-    Gson gson =
-        new GsonBuilder()
-            .excludeFieldsWithoutExposeAnnotation()
-            .registerTypeAdapter(Inventory.class, new InventorySerializer())
-            .registerTypeAdapter(PotionEffect.class, new PotionEffectSerializer())
-            .create();
     for (SRPlayer player : players.values()) {
-      dh.set(PLAYER_KEY + player.getUuid(), gson.toJson(player));
+      savePlayer(player);
     }
 
     players.clear();
@@ -61,7 +59,12 @@ public class PlayerManager extends Manager {
 
   @Nullable
   public SRPlayer getPlayer(UUID uuid) {
-    return players.get(uuid);
+    if (players.containsKey(uuid)) {
+      return players.get(uuid);
+    }
+    // load player data and returns it;
+
+    return loadPlayer(uuid);
   }
 
   public void addPlayer(@NotNull SRPlayer player) {
@@ -76,26 +79,31 @@ public class PlayerManager extends Manager {
     return players.containsKey(uuid);
   }
 
-  @EventHandler
-  public void onPlayerJoin(PlayerJoinEvent e) {
-    DataManager dm = DataManager.getInstance(DataManager.class);
-    if (dm == null) {
-      error("DataManager is null, Can't load player " + e.getPlayer().getName() + "'s data" + ".");
-      return;
+  public void savePlayer(SRPlayer player) {
+    if (dh == null) {
+      DataManager dm = DataManager.getInstance(DataManager.class);
+      if (dm == null) {
+        error("DataManager is null, Can't save player data.");
+        return;
+      }
+      dh = dm.getDataHandler();
     }
-    DataHandler dh = dm.getDataHandler();
+    // save all players
     Gson gson =
         new GsonBuilder()
-            .registerTypeAdapter(Inventory.class, new InventoryDeserializer())
-            .registerTypeAdapter(PotionEffect.class, new PotionEffectDeserializer())
             .excludeFieldsWithoutExposeAnnotation()
+            .registerTypeAdapter(Inventory.class, new InventorySerializer())
+            .registerTypeAdapter(PotionEffect.class, new PotionEffectSerializer())
             .create();
-    String json = dh.get(PLAYER_KEY + e.getPlayer().getUniqueId());
-    SRPlayer srPlayer = gson.fromJson(json, SRPlayer.class);
-    if (srPlayer == null) {
-      srPlayer = new SRPlayer(e.getPlayer());
-    }
+    dh.set(PLAYER_KEY + player.getUuid(), gson.toJson(player));
+  }
 
+  @EventHandler
+  public void onPlayerJoin(@NotNull PlayerJoinEvent e) {
+    SRPlayer srPlayer = loadPlayer(e.getPlayer().getUniqueId());
+    if (srPlayer == null) {
+      return;
+    }
     addPlayer(srPlayer);
 
     e.getPlayer().getInventory().clear();
@@ -106,6 +114,31 @@ public class PlayerManager extends Manager {
     e.getPlayer().updateInventory();
   }
 
+  @Nullable
+  private SRPlayer loadPlayer(UUID p) {
+    if (dh == null) {
+      DataManager dm = DataManager.getInstance(DataManager.class);
+      if (dm == null) {
+        error("DataManager is null, Can't save player data.");
+        return null;
+      }
+      dh = dm.getDataHandler();
+    }
+
+    Gson gson =
+        new GsonBuilder()
+            .registerTypeAdapter(Inventory.class, new InventoryDeserializer())
+            .registerTypeAdapter(PotionEffect.class, new PotionEffectDeserializer())
+            .excludeFieldsWithoutExposeAnnotation()
+            .create();
+    String json = dh.get(PLAYER_KEY + p);
+    SRPlayer srPlayer = gson.fromJson(json, SRPlayer.class);
+    if (srPlayer == null) {
+      srPlayer = new SRPlayer(p);
+    }
+    return srPlayer;
+  }
+
   @EventHandler
   public void onPlayerQuit(@NotNull PlayerQuitEvent e) {
     SRPlayer player = getPlayer(e.getPlayer().getUniqueId());
@@ -113,19 +146,7 @@ public class PlayerManager extends Manager {
       return;
     }
     // save for player
-    DataManager dm = DataManager.getInstance(DataManager.class);
-    if (dm == null) {
-      error("DataManager is null, Can't save player " + e.getPlayer().getName() + "'s data" + ".");
-      return;
-    }
-    DataHandler dh = dm.getDataHandler();
-    Gson gson =
-        new GsonBuilder()
-            .excludeFieldsWithoutExposeAnnotation()
-            .registerTypeAdapter(Inventory.class, new InventorySerializer())
-            .registerTypeAdapter(PotionEffect.class, new PotionEffectSerializer())
-            .create();
-    dh.set("sr.players." + e.getPlayer().getUniqueId(), gson.toJson(player));
+    savePlayer(player);
 
     removePlayer(e.getPlayer().getUniqueId());
   }

src/main/java/me/unurled/sacredrealms/sr/components/player/SRPlayer.java

@@ -29,6 +29,14 @@ public class SRPlayer {
   @Expose private List<PotionEffect> potionEffects;
   @Expose private Inventory inventory;
 
+  public SRPlayer(@NotNull UUID uuid) {
+    this.uuid = uuid;
+    Player player = Bukkit.getPlayer(uuid);
+    this.inventory = (player != null) ? player.getInventory() : null;
+    this.itemAttributes = new HashMap<>();
+    this.potionEffects = new ArrayList<>();
+  }
+
   public SRPlayer(@NotNull Player player) {
     this.uuid = player.getUniqueId();
     this.inventory = player.getInventory();
@@ -214,4 +222,8 @@ public class SRPlayer {
   public int getLevel() {
     return level;
   }
+
+  public void setLevel(int i) {
+    level = i;
+  }
 }

src/main/resources/plugin.yml

@@ -18,7 +18,11 @@ permissions:
     default: op
     description: When the player has permission for the command /attributes set
   sr.clientbuild:
+    default: op
     description: When the player has permission for the command /clientbuild
+  sr.level:
+    default: op
+    description: When the player has permission for the command /level
   sr.resetadventure:
     default: op
     description: When the player has permission for the command /resetadventure
@@ -28,5 +32,7 @@ commands:
     description: Set the attributes of the player.
   clientbuild:
     description: Set the client build of the player.
+  level:
+    description: Set the level of the player.
   resetadventure:
     description: Reset the adventure of the player