请教一下各位大佬， api 文档中关于 Comparable 接口的这段话是什么意思，看了好几遍也没懂。

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For the mathematically inclined, the relation that defines the natural ordering on a given class C is:

 {(x, y) such that x.compareTo(y) <= 0}.

The quotient for this total order is:

 {(x, y) such that x.compareTo(y) == 0}.

It follows immediately from the contract for compareTo that the quotient is an equivalence relation on C, and that the natural ordering is a total order on C. When we say that a class's natural ordering is consistent with equals, we mean that the quotient for the natural ordering is the equivalence relation defined by the class's equals(Object) method:

 {(x, y) such that x.equals(y)}.

2 replies 2022-03-30 12:23:57 +08:00

GuuJiang

Mar 22, 2022

你看不懂是因为里面出现了大量的数学名词及概念，不用深究，如果确实感兴趣的话可以去请教数学专业的人，我简单说下粗浅的理解，可能不准确，以专业人士的结论为准
整个这一段在说的就是 natural ordering 这个全序关系里的一个商构成一个等价关系，并且这个等价关系需要和 equals 构成的等价关系保持一致，至于关系、等价关系、关系的商这些就不展开了，去翻离散数学的书吧
说人话就是，x.compareTo(y) == 0 iff x.equals(y)

lr709

Mar 30, 2022

@GuuJiang 谢谢。