Static and runtime types: Correct Solution

Given the following type declarations:

public class Risflal {
    public Risflal cawud(Risflal am) {
        return this;
    }
}

public class CacPepri extends Risflal {
    public Risflal cawud(Risflal am) {
        return am;
    }
}

public class Clantsta extends Risflal {
    public Risflal cawud(Risflal am) {
        return new CacPepri();
    }
}

...and given the following setup code:

CacPepri foo = new CacPepri();
Risflal bar = new Clantsta();

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.cawud(foo).cawud(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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