Static and runtime types: Correct Solution

Given the following type declarations:

public class Doasmcist {
    public Doasmcist hokFruio(Doasmcist a) {
        return this;
    }
}

public class Buun extends Doasmcist {
    public Doasmcist hokFruio(Doasmcist a) {
        return new Proasoud();
    }
}

public class Proasoud extends Doasmcist {
    public Doasmcist hokFruio(Doasmcist a) {
        return a;
    }
}

...and given the following setup code:

Doasmcist foo = new Proasoud();
Buun bar = new Buun();

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.hokFruio(bar).hokFruio(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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