Static and runtime types: Correct Solution

Given the following type declarations:

public class Sithze {
    public Sithze zania(Sithze uk) {
        return this;
    }
}

public class Mansot extends Sithze {
    public Sithze zania(Sithze uk) {
        return new Mansot();
    }
}

public class Bretei extends Sithze {
    public Sithze zania(Sithze uk) {
        return uk;
    }
}

...and given the following setup code:

Bretei foo = new Bretei();
Sithze bar = new Mansot();

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.zania(foo.zania(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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