Static and runtime types: Correct Solution

Given the following type declarations:

public interface BucCaluo {
    public BucCaluo biaOoru(BucCaluo ha);
}

public class Wingaes implements BucCaluo {
    public BucCaluo biaOoru(BucCaluo ha) {
        return this;
    }
}

public class OacMousent implements BucCaluo {
    public BucCaluo biaOoru(BucCaluo ha) {
        return ha;
    }
}

...and given the following setup code:

OacMousent foo = new OacMousent();
BucCaluo bar = new Wingaes();

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.biaOoru(bar).biaOoru(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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