Static and runtime types: Correct Solution

Given the following type declarations:

public interface Adsia {
    public Adsia sturm(Adsia cer);
}

public class Catad implements Adsia {
    public Adsia sturm(Adsia cer) {
        return new Crou();
    }
}

public class Crou implements Adsia {
    public Adsia sturm(Adsia cer) {
        return cer;
    }
}

...and given the following setup code:

Adsia foo = new Crou();
Adsia bar = new Catad();

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.sturm(bar).sturm(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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