Expands DropperArenaHandler

Adds storage of currently playing players to DropperArenaHandler
Adds methods for getting, adding and removing arenas to DropperArenaHandler
Adds more annotations in some places

src/main/java/net/knarcraft/dropper/Dropper.java

@@ -1,11 +1,13 @@
 package net.knarcraft.dropper;
 
+import net.knarcraft.dropper.arena.DropperArenaHandler;
 import org.bukkit.plugin.java.JavaPlugin;
 
 @SuppressWarnings("unused")
 public final class Dropper extends JavaPlugin {
 
     private static Dropper instance;
+    private DropperArenaHandler arenaHandler;
 
     /**
      * Gets an instance of this plugin
@@ -20,6 +22,8 @@ public final class Dropper extends JavaPlugin {
     public void onEnable() {
         // Plugin startup logic
         instance = this;
+        this.arenaHandler = new DropperArenaHandler();
+        this.arenaHandler.loadArenas();
 
         //TODO: Keep track of whether players are in a dropper arena, and which arena they are in
         //TODO: Make an event listener that kicks players from an arena if they take damage (EntityDamageEvent).
@@ -47,6 +51,6 @@ public final class Dropper extends JavaPlugin {
 
     @Override
     public void onDisable() {
-        // Plugin shutdown logic
+
     }
 }

src/main/java/net/knarcraft/dropper/arena/DropperArena.java

@@ -4,23 +4,26 @@ import org.bukkit.Location;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
 
+/**
+ * A representation of one dropper arena
+ */
 public class DropperArena {
 
     /**
      * A name used when listing and storing this arena.
      */
-    private final String arenaName;
+    private final @NotNull String arenaName;
 
     /**
      * The location players are teleported to when joining this arena.
      */
-    private final Location spawnLocation;
+    private final @NotNull Location spawnLocation;
 
     /**
      * The location players will be sent to when they win or lose the arena. If not set, their entry location should be
      * used instead.
      */
-    private final Location exitLocation;
+    private final @Nullable Location exitLocation;
 
     /**
      * The velocity in the y-direction to apply to all players in this arena.
@@ -30,7 +33,7 @@ public class DropperArena {
     /**
      * The stage number of this arena. If not null, the previous stage number must be cleared before access.
      */
-    private final Integer stage;
+    private final @Nullable Integer stage;
 
     /**
      * Instantiates a new dropper arena

src/main/java/net/knarcraft/dropper/arena/DropperArenaHandler.java

@@ -2,26 +2,100 @@ package net.knarcraft.dropper.arena;
 
 import net.knarcraft.dropper.Dropper;
 import net.knarcraft.dropper.util.ArenaStorageHelper;
+import org.bukkit.entity.Player;
+import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.io.File;
 import java.io.IOException;
 import java.util.ArrayList;
+import java.util.HashMap;
 import java.util.List;
+import java.util.Map;
 import java.util.logging.Level;
 
+/**
+ * A handler that keeps track of all dropper arenas
+ */
 public class DropperArenaHandler {
 
-    List<DropperArena> arenas = new ArrayList<>();
-
     private static final File arenaFile = new File(Dropper.getInstance().getDataFolder(), "arenas.yml");
 
-    //TODO: Use this class to keep track of all created arenas. Saving and loading arenas is this class's responsibility
-    //TODO: Keep track of which players are in which arenas (should possibly be its own class, depending on complexity)
+    private List<DropperArena> arenas = new ArrayList<>();
+    private final Map<Player, DropperArena> arenaPlayers = new HashMap<>();
+
+    /**
+     * Registers that the given player has started playing in the given dropper arena
+     *
+     * @param player <p>The player that started playing</p>
+     * @param arena  <p>The arena the player is playing in</p>
+     */
+    public void registerPlayer(@NotNull Player player, @NotNull DropperArena arena) {
+        this.arenaPlayers.put(player, arena);
+    }
+
+    /**
+     * Removes this player from players currently playing
+     *
+     * @param player <p>The player to remove</p>
+     */
+    public void removePlayer(@NotNull Player player) {
+        this.arenaPlayers.remove(player);
+    }
+
+    /**
+     * Gets whether the given player is currently playing in an arena
+     *
+     * @param player <p>The player to check</p>
+     * @return <p>True if the player is currently in an arena</p>
+     */
+    public boolean isInArena(@NotNull Player player) {
+        return getArena(player) != null;
+    }
+
+    /**
+     * Gets the arena the given player is currently playing in
+     *
+     * @param player <p>The player to get arena for</p>
+     * @return <p>The player's active arena, or null if not currently playing</p>
+     */
+    public @Nullable DropperArena getArena(@NotNull Player player) {
+        return this.arenaPlayers.getOrDefault(player, null);
+    }
+
+    /**
+     * Adds a new arena
+     *
+     * @param arena <p>The arena to add</p>
+     */
+    public void addArena(@NotNull DropperArena arena) {
+        this.arenas.add(arena);
+        this.saveArenas();
+    }
+
+    /**
+     * Gets all known arenas
+     *
+     * @return <p>All known arenas</p>
+     */
+    public @NotNull List<DropperArena> getArenas() {
+        return new ArrayList<>(this.arenas);
+    }
+
+    /**
+     * Removes the given arena
+     *
+     * @param arena <p>The arena to remove</p>
+     */
+    public void removeArena(@NotNull DropperArena arena) {
+        this.arenas.remove(arena);
+        this.saveArenas();
+    }
 
     /**
      * Saves all current arenas to disk
      */
-    private void saveArenas() {
+    public void saveArenas() {
         try {
             ArenaStorageHelper.saveArenas(this.arenas, arenaFile);
         } catch (IOException e) {
@@ -33,7 +107,7 @@ public class DropperArenaHandler {
     /**
      * Loads all arenas from disk
      */
-    private void loadArenas() {
+    public void loadArenas() {
         this.arenas = ArenaStorageHelper.loadArenas(arenaFile);
     }
 

src/main/java/net/knarcraft/dropper/property/ArenaStorageKey.java

@@ -1,5 +1,7 @@
 package net.knarcraft.dropper.property;
 
+import org.jetbrains.annotations.NotNull;
+
 /**
  * A representation of each key used for storing arena data
  */
@@ -12,14 +14,14 @@ public enum ArenaStorageKey {
     STAGE("arenaStage"),
     ;
 
-    private final String key;
+    private final @NotNull String key;
 
     /**
      * Instantiates a new arena storage key
      *
      * @param key <p>The string path of the configuration key this value represents.</p>
      */
-    ArenaStorageKey(String key) {
+    ArenaStorageKey(@NotNull String key) {
         this.key = key;
     }
 
@@ -28,7 +30,7 @@ public enum ArenaStorageKey {
      *
      * @return <p>The string key representation.</p>
      */
-    public String getKey() {
+    public @NotNull String getKey() {
         return this.key;
     }
 

src/main/java/net/knarcraft/dropper/util/ArenaStorageHelper.java

@@ -84,7 +84,7 @@ public final class ArenaStorageHelper {
      * @param configurationSection <p>The configuration section containing arena data</p>
      * @return <p>The loaded arena, or null if invalid</p>
      */
-    private static @Nullable DropperArena loadArena(ConfigurationSection configurationSection) {
+    private static @Nullable DropperArena loadArena(@NotNull ConfigurationSection configurationSection) {
         String arenaName = configurationSection.getString(ArenaStorageKey.NAME.getKey());
         Location spawnLocation = (Location) configurationSection.get(ArenaStorageKey.SPAWN_LOCATION.getKey());
         Location exitLocation = (Location) configurationSection.get(ArenaStorageKey.EXIT_LOCATION.getKey());
@@ -104,7 +104,7 @@ public final class ArenaStorageHelper {
      * @param arenaName <p>The arena name to sanitize</p>
      * @return <p>The sanitized arena name</p>
      */
-    private static String sanitizeArenaName(String arenaName) {
+    public static @NotNull String sanitizeArenaName(@NotNull String arenaName) {
         return arenaName.toLowerCase().trim().replaceAll(" ", "_");
     }