why does java doesn't support multiple inheritance

One big problem with mulitple inheritance is what to do when both base classes implement a particular method differently. If the subclass doesn't override this method, what code should be called? This situation often arises when both base classes themselves extend from a common ancestor. In this case, a class hierarchy diagram would show a diamond pattern of classes.

This conflict doesn't exist for interfaces, because they don't provide implementations. It is perfectly acceptable for a class to implement two interfaces that define the same method. However, if the interfaces defined methods with identical signatures, but differing return types, there would still be a conflict.

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