2个班级之间有什么关系？

Question

If i have Class A and Class B what is the relation-ship between them if nothing else is stated (no HAS-A) relation-ship stated, is it Association?

class A{}
class B{}

Answer 1

There is no relation between those classes.

The only relationship that I can see is that they both implicitly inherit from Object .

Answer 2

它们是称为java.lang.Object的父类的子类，除此之外，没有可见的关系。

Answer 3

Based on the information you supplied. No, there is no relationship. In java, both inherit from the java.lang.Object. But from OO perspective, there is no relationship.

Class can be related in the following ways:

Aggregation - This is a has-a relationship where Class A has at least 1 field whose type is of classB Inheritance - This is an is-a relationship where a class B is a specialization of another class A. In this kind of relationship, the classB inherits all the behaviours of the class A.