Static and runtime types: Correct Solution

Given the following type declarations:

public interface Milzeck {
    public Milzeck paeIdcas(Milzeck acmo);
}

public class Edsprad implements Milzeck {
    public Milzeck paeIdcas(Milzeck acmo) {
        return acmo;
    }
}

public class Tarcin implements Milzeck {
    public Milzeck paeIdcas(Milzeck acmo) {
        return this;
    }
}

...and given the following setup code:

Milzeck foo = new Edsprad();
Milzeck bar = new Tarcin();

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.paeIdcas(bar.paeIdcas(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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