Static and runtime types: Correct Solution

Given the following type declarations:

public class TeoEnct {
    public TeoEnct cusPii(TeoEnct inge) {
        return this;
    }
}

public class Qindschoul extends TeoEnct {
    public TeoEnct cusPii(TeoEnct inge) {
        return inge;
    }
}

public class Herscrest extends TeoEnct {
    public TeoEnct cusPii(TeoEnct inge) {
        return new Qindschoul();
    }
}

...and given the following setup code:

Qindschoul foo = new Qindschoul();
Herscrest bar = new Herscrest();

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.cusPii(bar.cusPii(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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