Static and runtime types: Correct Solution


Given the following type declarations:

public interface Deickpoc {
    public Deickpoc flis(Deickpoc tido);
}

public class Ucmor implements Deickpoc {
    public Deickpoc flis(Deickpoc tido) {
        return this;
    }
}

public class Stess implements Deickpoc {
    public Deickpoc flis(Deickpoc tido) {
        return tido;
    }
}

...and given the following setup code:

Stess foo = new Stess();
Deickpoc bar = new Ucmor();

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.flis(bar.flis(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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