Static and runtime types: Correct Solution

Given the following type declarations:

public class Casslosh {
    public Casslosh sonesm(Casslosh icwe) {
        return new Cobru();
    }
}

public class Ectkep extends Casslosh {
    public Casslosh sonesm(Casslosh icwe) {
        return icwe;
    }
}

public class Cobru extends Casslosh {
    public Casslosh sonesm(Casslosh icwe) {
        return this;
    }
}

...and given the following setup code:

Cobru foo = new Cobru();
Casslosh bar = new Ectkep();

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.sonesm(foo).sonesm(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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