Why is there no multiple inheritance in Java, but implementing multiple interfaces is allowed?

java oop inheritance interface language-design
abson picture abson · Mar 25, 2010 · Viewed 128.9k times · Source

Java doesn't allow multiple inheritance, but it allows implementing multiple interfaces. Why?

Answer

Bozho picture Bozho · Mar 25, 2010

Because interfaces specify only what the class is doing, not how it is doing it.

The problem with multiple inheritance is that two classes may define different ways of doing the same thing, and the subclass can't choose which one to pick.

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