Need some help to clarify concepts

Question about the task

Food

Java Core, Level 4, Lesson 4

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I was able to do the task, but some things are not clear and I'd like if someone can help me clarify: When we declare

Selectable selectable = new Food();

What does exactly the created object references to? We cannot instantiate an interface... So, are we actually creating a Food object, but the only methods available are the ones belonging to the interface? Using the instanceof method like below, it return true on both, so why the onEat() method is not available from the selectable object?

selectable instanceof Selectable
selectable instanceof Food

Thanks!

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Vesa

Level 41 , Kaliningrad, Russia

13 January 2020, 21:47

>What does exactly the created object references to? we actually creating a Food object. >why the onEat() method is not available from the selectable object? the only methods available are the ones belonging to the interface The set of available methods is determined by variable type. To get access to onEat() method you have to do narrowing:

Selectable selectable = new Food();
Food food = (Food)selectable;