Static and runtime types: Correct Solution

Given the following type declarations:

public class Swel {
    public Swel asmro(Swel ku) {
        return this;
    }
}

public class Nelo extends Swel {
    public Swel asmro(Swel ku) {
        return new Closbae();
    }
}

public class Closbae extends Swel {
    public Swel asmro(Swel ku) {
        return ku;
    }
}

...and given the following setup code:

Closbae foo = new Closbae();
Swel bar = new Nelo();

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.asmro(foo.asmro(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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