Static and runtime types: Correct Solution

Given the following type declarations:

public class Coar {
    public Coar hasqer(Coar ci) {
        return ci;
    }
}

public class Elble extends Coar {
    public Coar hasqer(Coar ci) {
        return this;
    }
}

public class Elaw extends Coar {
    public Coar hasqer(Coar ci) {
        return new Elble();
    }
}

...and given the following setup code:

Elble foo = new Elble();
Coar bar = new Elaw();

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.hasqer(bar.hasqer(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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