Static and runtime types: Correct Solution

Given the following type declarations:

public interface Pruster {
    public Pruster hiuSioc(Pruster twul);
}

public class Saeun implements Pruster {
    public Pruster hiuSioc(Pruster twul) {
        return this;
    }
}

public class Prosh implements Pruster {
    public Pruster hiuSioc(Pruster twul) {
        return twul;
    }
}

...and given the following setup code:

Saeun foo = new Saeun();
Prosh bar = new Prosh();

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.hiuSioc(foo).hiuSioc(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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