Question

I have an Object and i just want to override equals method to compare two objects, I am not using any hashing collection anywhere in my program. In such case why there is a contract in hashCode and equals method i.e. If two objects are equal then they should have the same hashcode. shouldn t the general hashcode contract be case specific that if you want to put this object as key in some collection that uses hashing and then overrides it??

Answer 1

我要说的是,既然你不知道你(或更重要的是,另一个发展者)是否希望今后利用洗.来收集这些物品。这可能是直接的,也可能是间接的,即,你可以把你的反对转嫁给你没有写成的另一种方法,而其他方法则在执行工作中使用shed收集方法。

Answer 2

It s considered good practice (or mandatory) because you can t be sure nobody else (or you next month) will reuse you class.

需求相等的物体有资格用作关键用途,例如,需要背书。

You can see that as a convention, like the indentation or the cases of parameters and class names, but that this kind of convention that helps manage the code. Somebody seeing the equals method will rightly assume there is an hashcode method (maybe in a superclass). Don t surprise him (that s a general rule).

这就是说,你在帮助图书馆制定校车方法方面有很多帮助,而且你能够从你所了解的方法中汲取灵感(例如,在你检查和确定后,可以发挥功能,产生平等器具和散射法,但大多是可操作的)。

Answer 3

如果你重新界定<代码>等于,则你应重新界定<代码>hashCode/,但没有必要投入太多的努力。简言之,请看一下你喜欢的号码(8675309或不管怎样),简单地说,你们有<条码>。这样做将确保在插入你的标语时,将正确(尽管缓慢)收集 ha。

友情链接