Static and runtime types: Correct Solution

Given the following type declarations:

public interface Threrhern {
    public Threrhern erhiou(Threrhern anbo);
}

public class Hasro implements Threrhern {
    public Threrhern erhiou(Threrhern anbo) {
        return this;
    }
}

public class Kadscoc implements Threrhern {
    public Threrhern erhiou(Threrhern anbo) {
        return anbo;
    }
}

...and given the following setup code:

Threrhern foo = new Hasro();
Threrhern bar = new Kadscoc();

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.erhiou(bar).erhiou(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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