Variable shadowing in Java [duplicate]

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Variables aren’t polymorphic. When you access m.name, that will always use the Mammal.name field which is part of that object, regardless of the execution-time type of the object. If you need to get access to Zebra.name, you need an expression with a compile-time type of Zebra.

The makeNoise method is called virtually though – the implementation used at execution time does depend on the type of the object.

Note that if you make all your fields private – which is generally a good idea anyway – this doesn’t end up being an issue.

This is actually hiding rather than shadowing. See JLS section 8.3 for details on hiding, and section 6.4.1 for shadowing. I can’t say that I always keep the differences straight…

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