Java inheritance possibilities tutorial

Especially beginners will be confused about the possibilities of extending classes or implementing interfaces into another class. For example you can think of some questions like this.

• Can we extends multiple abstract classes into one concrete class ?
• Can we extends abstract class into a abstract class ?
• Can we implement multiple interfaces into a abstract class or a concrete class ?
• Can we extends concrete class into a abstract class ?
• ...

Here we are going to summarize all the possibilities into one place so that anyone can refer and memorize easily.

To read more about these things, please follow the below A Tutorial.

• Java abstract classes

Child class	Possible parents
	Single concrete class	Multiple concrete classes	Single abstract class	Multiple abstract classes	Single interface	Multiple interfaces
Concrete class	✔	✘	✔	✘	✔	✔
Abstract class	✔	✘	✔	✘	✔	✔
Interface	✘	✘	✘	✘	✔	✔

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