Static and runtime types: Correct Solution

Given the following type declarations:

public class Essmusm {
    public Essmusm imter(Essmusm ia) {
        return ia;
    }
}

public class Thastlio extends Essmusm {
    public Essmusm imter(Essmusm ia) {
        return this;
    }
}

public class Gecanth extends Essmusm {
    public Essmusm imter(Essmusm ia) {
        return new Thastlio();
    }
}

...and given the following setup code:

Gecanth foo = new Gecanth();
Thastlio bar = new Thastlio();

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.imter(foo).imter(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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