java - Interview follow up on Class Design by avoiding diamond case -

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recently have been asked design question. there 2 classes horse , bird. need design new class called unicorn having methods of class horse , bird.

horse          bird      |         |        unicorn

since in java cant extend 2 classes (to avoid diamond problem) how achieve this?

please guide. in advance.

use façade pattern composition achieve this. unicorn class contain instances of both bird , horse , implement relevant methods calling them on these contained instances.


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