Static and runtime types: Correct Solution

Given the following type declarations:

public class Ehee {
    public Ehee icess(Ehee as) {
        return new Riont();
    }
}

public class Centba extends Ehee {
    public Ehee icess(Ehee as) {
        return this;
    }
}

public class Riont extends Ehee {
    public Ehee icess(Ehee as) {
        return as;
    }
}

...and given the following setup code:

Riont foo = new Riont();
Ehee bar = new Centba();

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.icess(foo).icess(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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