文字冒险游戏。在Java中，一种认为我不在任何房间的方法

问：

嗨，就像我说的，我正在用 Java 制作一个文本冒险游戏，出于某种原因，除了制作它的方法之外，其他一切都有效，所以当我在一个房间里时，我可以在那里拿起任何物品。它认为我不在房间里并返回一个 null 值，即使我已经初始化了起始值。也很抱歉，我有多个班级可能有问题，我不会问我是否有任何关于如何解决它的想法。

这是我的主要游戏类，其中添加了 takeItems 方法和实际获取物品的函数：

  //Code to go from room to room
   static HashMap<String,Room> roomList = new HashMap<String, Room>();
   static String currentRoom;
   static PlayerStats player;
   static boolean isPlaying = true;

//Actual start
public static void main(String[] args) {
    PlayerStats playerStats = new PlayerStats();
    CombatTest combatTest = new CombatTest();
    setup(); 
        
    System.out.println("Welcome");
    lookAtRoom(true);       
    
    while(isPlaying) {
        String command = getCommand().toLowerCase();
        String word1 = command.split(" ")[0];           
        
        switch(word1.toLowerCase()) {
        case "n": case "s": case "w": case "e": case "u": case "d":
        case "north": case "south": case "west": case "east": case "up": case "down":
            moveToRoom(word1.charAt(0), playerStats, combatTest);
            break;
        case "i": case "inventory":
            showInventory(playerStats);
            break;
        case "look":
            lookAtRoom(true);
            break;
        case "hp": case "h":
            System.out.println("Your health is: " + playerStats.getHealth());
            break;
        case "take":
            if(command.split(" ").length < 2) {
                System.out.println("What do you want to take?");
            } else {
                String itemName = command.split(" ")[1];
                Room currentRoom = playerStats.getLocation();
                String result = takeItem(itemName, playerStats, currentRoom);
                System.out.println(result);
            }
            break;
        default: 
            System.out.println("Sorry, I don't understand that command");
            lookAtRoom(true);
            break;
        }
    }
}

 //Taking items
  public static String takeItem(String itemName, PlayerStats playerStats, Room 
  currentRoom) {

     if (currentRoom == null) {
         System.out.println("The player is not in a room!");
         return "";
     } 
      Item item = currentRoom.getItem(itemName);
      if (item == null) {
        return "There is no " + itemName + " in this room.";
     } else {
         playerStats.addItem(item);
         currentRoom.getItems().remove(item);
         return "You have taken the " + itemName + ".";
     } 
 }

 //This will crash if you move to a room that does not exist in the hashmap.
 public static void moveToRoom(char dir, PlayerStats playerStats, CombatTest combatTest) 
 {
     Room currentRoomObject = roomList.get(currentRoom);
     String newRoom = currentRoomObject.getExit(dir);

        if (newRoom.length() == 0) {
         System.out.println("You can't go that way");
         lookAtRoom(true);
         return;
      }

        ArrayList<Enemy> enemies = currentRoomObject.getEnemies();

      //Bandit Encounter
      if (newRoom.equals("dirty") && !enemies.isEmpty()) {
         System.out.println("As you step onto the dirty path, three bandits jump out 
       from the shadows and attack you!");
        for (int i = 0; i < enemies.size(); i++) {
            combatTest.run(enemies.get(i));
        }
        for (int i = enemies.size() - 1; i >= 0; i--) {
            if (enemies.get(i).getHealth() <= 0) {
                enemies.remove(i);
            }
        }
        if (enemies.isEmpty()) {
            System.out.println("You have defeated all the bandits in this area! You can 
            continue on your journey!");
        }
    }
   
   //Goblin encounter
    else if (newRoom.equals("cityGate") && !enemies.isEmpty()) {
        System.out.println("As you leave the clearing, three goblins jump out from the 
        bushes and attack you!");
        for (int i = 0; i < enemies.size(); i++) {
            combatTest.run(enemies.get(i));
        }
        for (int i = enemies.size() - 1; i >= 0; i--) {
            if (enemies.get(i).getHealth() <= 0) {
                enemies.remove(i);
            }
        }
        if (enemies.isEmpty()) {
            System.out.println("You have defeated all the goblins in your path! You can 
            continue on your journey!");
        }
    }
   
   //Going to the new room
    currentRoom = newRoom;
    lookAtRoom(true);
}
    
  //looking at the rooms
  private static void lookAtRoom(boolean b) {
     Room rm = roomList.get(currentRoom);
     System.out.println("\n== " + rm.getTitle() + " ==");
     System.out.println(rm.getDesc());
  }
    

  private static void showInventory(PlayerStats playerStats) {
     ArrayList<Item> inventory = playerStats.getInventory();
     if (inventory.isEmpty()) {
         System.out.println("Your inventory is empty");
     } else {
         System.out.println("Inventory:");
         for (Item item : inventory) {
             System.out.println("- " + item.getName());
         }
      }
     lookAtRoom(true);
  }

   static Scanner sc = new Scanner(System.in);
   static String getCommand() {
    System.out.print("=> ");        
    String text = sc.nextLine();
    System.out.println(" ");
    if (text.length() == 0) text = "qwerty"; //default command      
    return text;
  }

  static void setup() {
        Room.setupRooms(roomList);
        currentRoom = "clearing"; //where you start
   }
 }

这是房间类，它处理从一个房间到另一个房间以及物品实际添加到房间的位置，现在我只有一把匕首和一些硬币在“空地”中，所以我可以测试：

  import java.util.ArrayList;
  import java.util.HashMap;

  class Room {

        private String title;
        private String description; 
        private String N,S,E,W;
        private ArrayList<Item> itemList = new ArrayList<Item>();
        public ArrayList<Enemy> enemyList = new ArrayList<Enemy>(); // added for enemies 
 in the room

     public ArrayList<Enemy> getEnemyList() {
            return enemyList;
        }
     
     //Itemlist thing
     public void addItem(Item item) {
            itemList.add(item);
        }
     
     public Item getItem(String itemName) {
            for (Item item : itemList) {
                if (item.getName().equals(itemName)) {
                    return item;
                }
            }
            return null;
        }

        public ArrayList<Item> getItems() {
            return itemList;
        }
     
    Room(String t, String d) {
        title = t;
        description = d;
    }
    
    private void setExits(String N, String S, String W, String E) {
        this.N = N;
        this.S = S;
        this.W = W;
        this.E = E;     
    }
    
    String getExit(char c) {
        switch (c) {
        case 'n': return this.N;
        case 's': return this.S;
        case 'w': return this.W;
        case 'e': return this.E;
        default: return null;
        }
    }
    
    String getTitle() {return title;}
    String getDesc() {return description;}
    
    public ArrayList<Enemy> getEnemies() {
        return this.enemyList;
    }
    
    public static Room getRoom(String name, ArrayList<Room> roomList) {
        for (Room room : roomList) {
            if (room.getTitle().equals(name)) {
                return room;
            }
        }
        return null;
    }
    
    // done at the beginning of the game
    static void setupRooms(HashMap <String, Room> roomList) {
        
        //Going north into the city routes
        Room r = new Room("Clearing", "You are in a small clearing in a" +
    " forest. You hear birds singing. You can also hear faint voices to the north of 
       you. You also notice a strange rock.");
        r.enemyList.add(new Goblin()); // add three goblins to the clearing
        r.enemyList.add(new Goblin());
        r.enemyList.add(new Goblin());
        
        r.addItem(new Item("Coins", "Shiny gold coins that can be traded for goods", 5, 
        0));
        r.addItem(new Item("Dagger", "A sturdy dagger that does 1 damage", 1, 1));
        
        r.setExits("cityGate", "", "", "");
        roomList.put("clearing", r);
        
        
        r = new Room("City Gates", "You see the gates of a city as you" +
        " approach the voices, there are guards outside the gates. You also see a 
        suspicious looking man at the edge of the forest to the west.");
        r.setExits("market", "clearing", "susman", "");
        roomList.put("cityGate", r);
        
        //all the different shops and the market place.
        r = new Room("Market Place", "When you enter the city you see a "+
        "busy marketplace, to the west of you is a supplies shop," +
        " to the east of you there is a weapons shop. You can see a large castle in the 
        distance northwards.");
        r.setExits("ornate", "cityGate", "supplyMerchant", "weaponsMerchant");
        roomList.put("market", r);
        
        r = new Room("Suspicious Man", "As you approach the man he notices you and 
         quietly says \"Hey! Hey you! Over here!\" He motions for you to enter a forest 
        clearing and says \"Hello stranger! I have some... not so legally aquired items 
        for sale. So what're you buyin?\" ");
        r.setExits("", "", "", "cityGate");
        roomList.put("susman", r);
        
        r = new Room("Weapons Merchant", "As you walk towards the weapons merachant he 
        says \"Welcome good sir! I have the finest weapons in the whole realm! Best 
        prices too! Now look around and see what you are interested in! \" ");
        r.setExits("", "", "market", "");
        roomList.put("weaponsMerchant", r);
        
        r = new Room("Supplies Merchant", "As you walk towards the weapons merachant he 
        says \"Hello sir! I have a variety of different items for sale. Please look to 
         your hearts content and buy whatever your heart desires.\" ");
        r.setExits("", "", "", "market");
        roomList.put("supplyMerchant", r);
        
        //Towards the castle/dungeon
        r = new Room("Ornate Path", "As you walk towards the castle you walk along an 
        ornate path, it is made of marble and has fancy looking lanterns hanging above 
        to provide light. You reach a branch in the road, you can either continue north 
        towards the castle, or step off the main path eastward into a much less ornate, 
        dirty looking path. You cannot tell where the dirty looking path leads.");
        r.enemyList.add(new Bandit()); // add three bandits to the clearing
        r.enemyList.add(new Bandit());
        r.enemyList.add(new Bandit());
        r.setExits("castle", "market", "", "dirty");
        roomList.put("ornate", r);
        
        //Dungeon Route
        r = new Room("Dirty Path", "As you walk along the dirty path you evntually see a 
        small building that has a staircase leading downwards. This is your last chance 
        to turn back.");
        r.setExits("", "", "ornate", "dungeonEnt");
        roomList.put("dirty", r);
        
        r = new Room("Dungeon Entrance", "You enter the dungeon and see a few cells with 
        skeletons in them and dried blood stains on the floor, you hear voices coming 
        from behind a door to the south, and the hallway continues to the east.");
        r.setExits("", "southDugDoor", "", "dungeon");
        roomList.put("dungeonEnt", r);
        
        r = new Room ("Southern Dungeon Door","You can hear some voices behind the door 
        but would have to get closer to understand, or you could go back to the main 
        hall.");
        r.setExits("dungeonEnt", "", "", "");
        roomList.put("southDugDoor", r);
        
        r = new Room("Dungeon", "You enter the middle of the hall each side of the hall 
        is lined with cells with bodies and fresher looking blood in them. Ahead of you, 
        you can hear screams and someone talking to themselves as well, though you 
        cannot hear what");
        r.setExits("", "", "dungeonEnt", "torturer");
        roomList.put("dungeon", r);
        
        r = new Room("Boss Room: The Torturer", "As you enter the room you see a man in 
        a hood injecting something into a screaming man. The hooded man then says 
        \"Hmmm, no not this one. Too painful. someone will hear the king scream when he 
         dies.\" The man then turns around and notices you, as the screaming man behind 
         him dies. The strange man then says \"Are you someone sent by the king, or just 
         an unlucky wanderer? No matter, you will die either way!\" He then pulls out 
         two poison covered knives and attacks you!");
        r.setExits("", "", "dungeon", "");
        roomList.put("torturer", r);
        
        //Castle Route
        r = new Room("Castle Pathway", "As you walk towards the castle, you are happy 
        that you might finally get some work from the king. This is your last chance to 
        turn back.");
        r.setExits("castleEnt", "ornate", "", "");
        roomList.put("castle", r);
        

        r = new Room("Castle Entrance", "As you walk up to the entrance of the castle, 
        you can see a large staircase and walking down the staircse towards you is an 
        armoured knight.");
        r.setExits("throne", "", "", "");
        roomList.put("castleEnt", r);
        
        
        r = new Room("Boss Room: The Assassin","");
        r.setExits("", "", "", "");
        roomList.put("Throne", r);
    
      }
   }

下面是 playerStats 类，它具有用于位置的 setter 和 getters：

         TextAdvenureGame;
         import java.util.ArrayList;

 public class PlayerStats {
   private int baseDamage = 1;
   private int health = 10;
   private Weapon equippedWeapon;
   private Room location;
   private ArrayList<Item> inventory;

 public PlayerStats() {
    this.equippedWeapon = null;
    this.inventory = new ArrayList<Item>();
    this.location = location;
  }

  public void Stats(int baseDamage, int health) {
      this.baseDamage = baseDamage;
      this.health = health;
 }

 public void equipWeapon(Weapon weapon) {
     this.equippedWeapon = weapon;
 }

 public int getDamage() {
     if (equippedWeapon == null) {
         return baseDamage;
     } else {
         return baseDamage + equippedWeapon.getDamage();
     }
 }

 public int getHealth() {
     return health;
 }

 public boolean isAlive() {
     return health > 0;
 }

 public void takeDamage(int damage) {
     health -= damage;
     if (health < 0) {
          health = 0;
     }
 }

  public ArrayList<Item> getInventory() {
     return inventory;
  }

  public void setInventory(ArrayList<Item> inventory) {
      this.inventory = inventory;
  }

  public void addItem(Item item) {
      inventory.add(item);
  }

  public void setLocation(Room currentRoom) {
      this.location = currentRoom;
  }

  public Room getLocation() {
      return location;
     }
  }

`

再次，对不起，编码问题很长，但我真的没有想法。它现在正在做的是，每当我玩游戏时，它都会这样做： 欢迎

== 清算 == 你在森林里的一小块空地上。你听到鸟儿唱歌。你也可以听到你北方微弱的声音。你还注意到一块奇怪的岩石。 =>拿匕首

玩家不在房间里！