问题描述
我正在编写一个简短的程序,但我遇到了问题.
Im writing a short program and I have a problem.
有更多细节问题.
我有功能
public CardStck from(Card card)
int pos = this.cardList.indexOf(card);
如您在调试屏幕上看到的,本例中的
card是Card(value = 5,color ="D")-甚至在此card.im卡中我正在搜索5(D)(菱形5卡). pos的值为-1(未找到)
card for this example is Card(value=5, color="D")- as u see on the debugging screenEven there is that card im searching for 5(D) (diamond 5 card) in this.cardList the value of pos is -1 (not found)
谁能告诉我问题出在哪里吗?
Could anyone tell me where the problem is?
推荐答案
在卡片类中,实现等于"方法,如下所示:
In your card class, implement the "equals" method, like this:
@Override
public boolean equals(Object t){
if(!(t instanceof Card)){
return false;
}
Card c = (Card)t;
//Compare however you want, ie
return (c.getValue() == this.getValue()) & (c.getColor().equals(this.getColor());
}
您可能还需要包含其他一些null检查或安全性内容,例如确保颜色不为null等,但这是通常的想法.
there may be some other null checks or safety stuff you want to include, like making sure color isn't null etc, but that's the general idea.
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