Static and runtime types: Correct Solution

Given the following type declarations:

public interface Cubhoib {
    public Cubhoib caeIlo(Cubhoib fimi);
}

public class Singen implements Cubhoib {
    public Cubhoib caeIlo(Cubhoib fimi) {
        return new Singen();
    }
}

public class Entmoe implements Cubhoib {
    public Cubhoib caeIlo(Cubhoib fimi) {
        return fimi;
    }
}

...and given the following setup code:

Cubhoib foo = new Entmoe();
Cubhoib bar = new Singen();

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.caeIlo(foo).caeIlo(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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