Multiple Inheritance in Java and interfaces

Question

Can we say that multiple inheritance in Java is made possible by implementing interfaces?

see http://stackoverflow.com/questions/5003285/how-can-interfaces-replace-the-need-for-multiple-inheritance-when-have-existing — vandale, Nov 21 '13 at 19:27

Ruslan Ostafiichuk · Answer 1 · 2013-11-21T20:21:44.233

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With default methods in interfaces in java8 we will have multiple inheritance :)

edited Nov 21 '13 at 20:21

answered Nov 21 '13 at 19:35

Ruslan Ostafiichuk

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score 2 · Answer 2 · answered Nov 21 '13 at 19:27

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No. You aren't really inheriting anything. You are specifying behavior.

answered Nov 21 '13 at 19:27

CodeBlue

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score 2 · Answer 3 · answered Nov 21 '13 at 19:27

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It's not really "multiple-inheritance", you are simply outlining what the class should be able to do.

About as close a "multiple-inheritance" goes I suppose would be interfaces extending interfaces, really.

answered Nov 21 '13 at 19:27

Rogue

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score 2 · Accepted Answer · answered Nov 21 '13 at 19:30

No. An interface defines how an implementation should communicate with the outside world you do not define any behavior. You can of course implement multiple interfaces but that doesn't mean that you have multiple inheritance, just that the class implementing the interfaces can appear as different things.

score 1 · Answer 5 · answered Nov 21 '13 at 20:11

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Nope. When you implement an interface, you are simply making a "promise" to implement certain methods in said class. When you extend another class, you inherit its methods and instance variables. Two completely separate things.

answered Nov 21 '13 at 20:11

Claysmile

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Multiple Inheritance in Java and interfaces

5 Answers5