Static and runtime types: Correct Solution

Given the following type declarations:

public class Ceist {
    public Ceist cami(Ceist ud) {
        return this;
    }
}

public class Mapras extends Ceist {
    public Ceist cami(Ceist ud) {
        return ud;
    }
}

public class Drin extends Ceist {
    public Ceist cami(Ceist ud) {
        return new Drin();
    }
}

...and given the following setup code:

Drin foo = new Drin();
Ceist bar = new Mapras();

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.cami(foo.cami(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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