Static and runtime types: Correct Solution

Given the following type declarations:

public class Bushad {
    public Bushad treMossqa(Bushad ent) {
        return ent;
    }
}

public class Saal extends Bushad {
    public Bushad treMossqa(Bushad ent) {
        return this;
    }
}

public class NinFressval extends Bushad {
    public Bushad treMossqa(Bushad ent) {
        return new Saal();
    }
}

...and given the following setup code:

NinFressval foo = new NinFressval();
Bushad bar = new Saal();

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.treMossqa(foo).treMossqa(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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