Referencing an interface from ArrayList

Question

I am having trouble understanding ((Edible)objects[i]).howToEat() at line 7 in the java code example given below. Edible is an interface which contains abstract method howToEat() and I understand that this is a reference to an array but how is the "Edible" interface being referenced in this statement?

public class TestEdible {
    
    public static void main(String[] args) {
        Object[] objects = {new Tiger(), new Chicken(), new Apple()};
        for (int i= 0; i <objects.length; i++) {
            if(objects[i] instanceof Edible) {
                System.out.println( ((Edible)objects[i]).howToEat() );
            }
            else {
                System.out.println("Object is not edible");
            }
        }
    }
}

Please explain if the interface is being referenced from an object or array in the statement, or if this is just a syntax related to interfaces that I may not be familiar with. I am not well versed in use of interfaces so I may be overlooking something, thank you.

Answer 1

((Edible)objects[i]) syntax means cast objects[i] to Edible. It could be just (Edible)objects[i]. It's wrapped into brackets just to inline it for the following method call.

So the code

if(objects[i] instanceof Edible) {
   System.out.println( ((Edible)objects[i]).howToEat() );
}

could be rewritten as simpler to read:

if(objects[i] instanceof Edible) {
   Edible currentObject = (Edible) objects[i];
   System.out.println(currentObject.howToEat());
}

So you're basically telling the Java compiler that you want to threat object[i] as an Edible because you know what you do and you already checked it with instanceof above.

As @daniu noted, with Java 16 you can have another syntax for that:

if(objects[i] instanceof Edible currentObject) {
   System.out.println(currentObject.howToEat());
}