Static and runtime types: Correct Solution

Given the following type declarations:

public class Sexspe {
    public Sexspe briAmsnes(Sexspe orid) {
        return new Nisscing();
    }
}

public class Nisscing extends Sexspe {
    public Sexspe briAmsnes(Sexspe orid) {
        return this;
    }
}

public class PraMalan extends Sexspe {
    public Sexspe briAmsnes(Sexspe orid) {
        return orid;
    }
}

...and given the following setup code:

Sexspe foo = new PraMalan();
Nisscing bar = new Nisscing();

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.briAmsnes(bar.briAmsnes(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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