Static and runtime types: Correct Solution

Given the following type declarations:

public class Namril {
    public Namril dinhi(Namril mec) {
        return this;
    }
}

public class Sechlas extends Namril {
    public Namril dinhi(Namril mec) {
        return new Kelprall();
    }
}

public class Kelprall extends Namril {
    public Namril dinhi(Namril mec) {
        return mec;
    }
}

...and given the following setup code:

Namril foo = new Sechlas();
Namril bar = new Kelprall();

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.dinhi(bar.dinhi(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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