Java - 將類實例返回到不同類的方法？

Question

我是初學者，嘗試過搜索，但沒有任何結果，抱歉。 我有 2 個課程，我不知道如何鏈接獎勵硬幣（oneCoin/twoCoin/threeCoin），以便如果調用，它會將硬幣添加到 Bag 庫存中。 回報也可能不正確。

public class Bag {
    private int oneCoin;
    private int twoCoin;
    private int threeCoin;
    
    //etc
}

public class Thief {
     public Thief(String name, int level) {
        this.name = name;
        this.health = level * 100;
        this.level = level;
    }
    
    //problem code
    public Bag rewardCoins(){
        oneCoin =+ (int)(level-Math.random()*level/6);
        twoCoin =+ (int)(level-Math.random()*level/2);
        threeCoin =+ (int)((level-level/2)-Math.random()*(level-level/2));
        return rewardCoins();
    }
}

不尋求即時幫助，我只是不知道我應該閱讀什么來弄清楚。

編輯：我可能解釋得不好——我不能使用二傳手，因為 Bag 庫存中已經有東西了。 當小偷被“擊敗”時，我想將硬幣添加到庫存中。 就像丟掉戰利品一樣。 我不知道如何訪問 Thief 中的私有字段 one/two/threeCoin 以將它們添加到另一個類。 它們是 2 個不同的類，Thief.java 和 Bag.java

第二次編輯：對於閱讀本文的任何人，答案是將屬性和返回值更改為-

public Bag rewardCoins(){
        int one = (int)(level-Math.random()*level/6);
        int two = (int)(level-Math.random()*level/2);
        int three = (int)((level-level/2)-Math.random()*(level-level/2));
        return (new Bag(one, two, three));
}

Answer 1

你可能想要這樣的東西：

public class Thief {
    private final String name;
    private final int health;
    private final int level;

    public Thief(String name, int level) {
        this.name = name;
        this.health = level * 100;
        this.level = level;
    }

    public Bag rewardCoins(Bag bag){
        int oneCoin = bag.getOneCoin();
        int twoCoin = bag.getTwoCoin();
        int threeCoin = bag.getThreeCoin();

        oneCoin =+ (int)(level-Math.random()*level/6);
        twoCoin =+ (int)(level-Math.random()*level/2);
        threeCoin =+ (int)((level-level/2)-Math.random()*(level-level/2));

        Bag result = new Bag();
        result.setOneCoin(oneCoin);
        result.setTwoCoin(twoCoin);
        result.setThreeCoin(threeCoin);

        return result;
    }
}

或這個：

public class Thief {
    private final String name;
    private final int health;
    private final int level;
    private Bag bag;

    public Thief(String name, int level) {
        this.name = name;
        this.health = level * 100;
        this.level = level;
    }

    public Bag rewardCoins(){
        int oneCoin = bag.getOneCoin();
        int twoCoin = bag.getTwoCoin();
        int threeCoin = bag.getThreeCoin();

        oneCoin =+ (int)(level-Math.random()*level/6);
        twoCoin =+ (int)(level-Math.random()*level/2);
        threeCoin =+ (int)((level-level/2)-Math.random()*(level-level/2));

        Bag result = new Bag();
        result.setOneCoin(oneCoin);
        result.setTwoCoin(twoCoin);
        result.setThreeCoin(threeCoin);

        return result;
    }
}

Answer 2

這得看情況。 查看您的代碼，我可以假設您希望小偷將硬幣獎勵給小偷之間共享的庫存。 在這種情況下，您可以將其作為小偷的變量並將其作為構造函數的參數傳遞。 這樣所有的竊賊都可以訪問同一個 Bag 對象。

public class Bag {
private int oneCoin;
private int twoCoin;
private int threeCoin;

//getters and setters
}

public class Thief {
private Bag bag;
 public Thief(String name, int level,final Bag bag) {
    this.name = name;
    this.health = level * 100;
    this.level = level;
    this.bag=bag;
}


public void rewardOneCoin(){

    bag.setOneCoin(bag.getOneCoin()+ (int)(level-Math.random()*level/6))
   
    
}

// Appropriate functions for two and three coins
}

如果你能給我更多的背景信息，我可能會為你提供更多幫助