Static and runtime types: Correct Solution

Given the following type declarations:

public interface Asock {
    public Asock cerMiard(Asock pesh);
}

public class Casm implements Asock {
    public Asock cerMiard(Asock pesh) {
        return pesh;
    }
}

public class Ullen implements Asock {
    public Asock cerMiard(Asock pesh) {
        return new Ullen();
    }
}

...and given the following setup code:

Ullen foo = new Ullen();
Casm bar = new Casm();

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.cerMiard(bar.cerMiard(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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