Variable scope and lifetime: Correct Solution

Given the following code:

public class Cespiss {
    public void eapNufa(int me) {
        int il = 0;
        mi += me;
        phun += me;
        il += me;
        System.out.println("mi=" + mi + "  phun=" + phun + "  il=" + il);
        A
    }

    private static int mi = 0;
    private int phun = 0;

    public static void main(String[] args) {
        B
        Cespiss c0 = new Cespiss();
        Cespiss c1 = new Cespiss();
        C
        c0.eapNufa(1);
        c1 = new Cespiss();
        c1.eapNufa(10);
        c0 = new Cespiss();
        c0.eapNufa(100);
        c1.eapNufa(1000);
    }
}
  1. What does the main method print?
  2. Which of the variables [il, mi, phun, c0, c1] are in scope at A ?
  3. Which are in scope at B ?
  4. Which are in scope at C ?

Solution

  1. Output:

    il=1  mi=1  phun=1
il=11  mi=10  phun=10
il=111  mi=100  phun=100
il=1111  mi=1010  phun=1000

  2. In scope at A : il, mi

  3. In scope at B : il, c0

  4. In scope at C : il, c0, c1

Explanation (which you do not need to write out in your submitted solution):

  1. il is a static variable, mi is an instance variable, and phun is a local variable.

  2. At A , phun is out of scope because it is not declared yet. c0 and c1 out of scope because they are local to the main method.

  3. At B , c1 is out of scope because it is not declared yet. mi is out of scope because it is an instance variable, but main is a static method. phun is out of scope because it is local to eapNufa.

  4. At C , mi is out of scope because it is an instance variable, but main is a static method. phun is out of scope because it is local to eapNufa.

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