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接口是否可继承接口?抽象类是否可实现(implements)接口?抽象类是否可继承实体类(concreteclass)?

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正确答案:

答: 1、接口是否可继承接口? 答:不可以。接口是要被实现而不是被继承的,加入你用词不当,问接口是否可实现接口,答案仍然是不能,因为接口里面的方法必 须全部是抽象方法,接口 A 实现了接口 B,那么 A 就要重写 B 的抽象方法,重写了之后, A 的性质也就不是接口 A 了,变成了抽象 类 A。

2、抽象类是否可实现接口? 答:可以。正如第一题所说。

3、抽象类是否可继承实体类? 答:可以

答案解析:

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