Static and runtime types: Correct Solution

Given the following type declarations:

public interface Dunchru {
    public Dunchru irmJenra(Dunchru peo);
}

public class Sprud implements Dunchru {
    public Dunchru irmJenra(Dunchru peo) {
        return this;
    }
}

public class Chansi implements Dunchru {
    public Dunchru irmJenra(Dunchru peo) {
        return new Sprud();
    }
}

...and given the following setup code:

Dunchru foo = new Chansi();
Dunchru bar = new Sprud();

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.irmJenra(bar.irmJenra(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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