檢查，如果用戶輸入包含項目

Question

在我的文字冒險遊戲的命令之一是「拿」這需要用戶輸入兩個字母「T」那就是在房間裏，他們是一個項目英寸
我已經採取了這個輸入，並將其分割成命令和項目，但我遇到了與if語句的麻煩。我有第一部分檢查命令部分是否等於'T'，但我還必須檢查這個輸入是否有「item」部分。我嘗試使用.isEmpty()和!= null以及使用.contains()。

這裏是我的代碼：

public Command getCommandFromResponse(String response) throws IllegalArgumentException{ 
    String[] split = response.split(" "); 

    if (split.length < 1){ 
     throw new IllegalArgumentException("Invalid command."); 
    } 

    Command command = new Command(split[0]); 
    if (split.length >= 2) { 
     command.setItem(split[1]); 
    } 
    return command; 
} 

這是take方法：

else if(userCommand.command.equalsIgnoreCase("T") && /*if userCommand contains an item*/){     
    //Split the input String into two parts, command and item 
    userCommand = getCommandFromResponse(userInput.nextLine()); 
    if (locale.item != null) { 
     if (userCommand.item.equalsIgnoreCase(locale.item.itemName)) { 
      //add the item to the player's inventory 
      player1.inventory.add(locale.item); 
      System.out.println("\tA " + locale.item + " was added to your inventory"); 
      System.out.println("\n\tYou can view your inventory by pressing 'I' or drop an item by pressing 'D'."); 
      if (locale.item.itemName.equals("map")) { 
       System.out.println("\n\tTo view the map press 'M'."); 
      } 
      //Add the item's worth to the score and set the items worth to zero to prevent double scoring 
      player1.score += locale.item.value; 
      System.out.println("\n\t" + locale.item.value + " points have been added to your score."); 
      System.out.println("\n\tThis is your current score: "+player1.score); 
      //remove the item from the current location 
      locale.item = null; 
      break; 
     } else { 
      System.out.println("\n\tThat item is not at this location."); 
     } 
    } else { 
     System.out.println("\n\tThere is no item to pick up here"); 
    } 
}//End of Take 

這是我的命令類：

public class Command { 

    String command; 
    String item; 
    public Command(String comm){ 
     command = comm; 
    } 

    public Command(String comm, String item){ 
     this.command = comm; 
     this.item = item; 
    } 

    public void setCommand(String command){ 
     this.command = command; 
    } 

    public void setItem(String item){ 
     this.item = item; 
    } 

    public String getCommand(){ 
     return this.command; 
    } 

    public String getItem(){ 
     return this.item; 
    } 

    public String toString(){ 
     return this.command + ":" + this.item; 
    } 

} 

這是我的項目：

//Items {itemName, itemDes} 
    static Item[] items = { 
      new Item ("map","a layout of your house", 10), 
      new Item ("battery", "a double A battery", 5), 
      new Item ("flashlight", "a small silver flashlight", 10), 
      new Item ("key", "this unlocks some door in your house", 15), 
    }; 

我有更多的代碼，如果這不清楚。

Answer 1

我的建議是做它的方式如下：

變化

if (userCommand.item.equalsIgnoreCase(locale.item.itemName)) { 

到

if (userCommand.item!=null && userCommand.item.equalsIgnoreCase(locale.item.itemName)) { 

這是最簡單的方法，如果有這將不會拋出異常命令中沒有項目。

（我很抱歉，如果這不是你的問題，但是這是我想你所指的問題。）你怎麼有存儲