Static and runtime types: Correct Solution

Given the following type declarations:

public class Adist {
    public Adist ibass(Adist e) {
        return e;
    }
}

public class Rimel extends Adist {
    public Adist ibass(Adist e) {
        return this;
    }
}

public class Rostdont extends Adist {
    public Adist ibass(Adist e) {
        return new Rostdont();
    }
}

...and given the following setup code:

Rimel foo = new Rimel();
Rostdont bar = new Rostdont();

Part 1

Draw an AST for the following expression, labeling the static type (a.k.a. compile-time type) of each node in the tree:

foo.ibass(bar.ibass(bar))

(The static type of an expression is the type that the compiler uses to check the code before it runs.)

Solution

Part 2

Draw an AST for the same expression, this time labeling the runtime type of each node in the tree.

(The runtime type of an expression is the type of the actual value that appears when the code runs.)

Solution

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