Static and runtime types: Correct Solution

Given the following type declarations:

public class Imish {
    public Imish possat(Imish ae) {
        return this;
    }
}

public class Scect extends Imish {
    public Imish possat(Imish ae) {
        return new Hiash();
    }
}

public class Hiash extends Imish {
    public Imish possat(Imish ae) {
        return ae;
    }
}

...and given the following setup code:

Hiash foo = new Hiash();
Imish bar = new Scect();

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.possat(bar.possat(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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