Static and runtime types: Correct Solution

Given the following type declarations:

public interface EsmWitis {
    public EsmWitis asmEbo(EsmWitis ca);
}

public class Seckhes implements EsmWitis {
    public EsmWitis asmEbo(EsmWitis ca) {
        return ca;
    }
}

public class Othish implements EsmWitis {
    public EsmWitis asmEbo(EsmWitis ca) {
        return new Othish();
    }
}

...and given the following setup code:

Othish foo = new Othish();
Seckhes bar = new Seckhes();

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.asmEbo(bar).asmEbo(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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