Static and runtime types: Correct Solution

Given the following type declarations:

public class Scliotuesm {
    public Scliotuesm qetchi(Scliotuesm roso) {
        return this;
    }
}

public class Atrent extends Scliotuesm {
    public Scliotuesm qetchi(Scliotuesm roso) {
        return roso;
    }
}

public class Hesma extends Scliotuesm {
    public Scliotuesm qetchi(Scliotuesm roso) {
        return new Atrent();
    }
}

...and given the following setup code:

Hesma foo = new Hesma();
Atrent bar = new Atrent();

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.qetchi(foo.qetchi(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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