[NP] SwapTest (Question)

import java.util.concurrent.atomic.AtomicInteger;

public class SwapTest {

    /*

    int Primitives
    ===================
    Original numbers:
    zero = 0     one = 1
    Using swapPrimitives()
    zero = 0     one = 1
    Without using a function to swap
    zero = 1     one = 0

    Integer Objects
    ===================
    Original numbers:
    zero = 0     one = 1
    Using swapIntegers()
    zero = 0     one = 1
    Without using a function to swap
    zero = 1     one = 0

    */

    public static void main(String args[]) {
        int zero = 0;
        int one = 1;
        System.out.println("");
        System.out.println("int Primitives");
        System.out.println("===================");
        System.out.println("Original numbers: ");
        System.out.println(String.format("zero = %d \t one = %d", zero, one));
        swapPrimitives(zero, one);
        System.out.println("Using swapPrimitives()");
        System.out.println(String.format("zero = %d \t one = %d", zero, one));
        int temp = zero;
        zero = one;
        one = temp;
        System.out.println("Without using a function to swap");
        System.out.println(String.format("zero = %d \t one = %d", zero, one));

        System.out.println("");
        System.out.println("Integer Objects");
        System.out.println("===================");
        Integer Zero = new Integer(0);
        Integer One = new Integer(1);
        System.out.println("Original numbers: ");
        System.out.println(String.format("zero = %d \t one = %d", Zero.intValue(), One.intValue()));
        swapIntegers(Zero, One);
        System.out.println("Using swapIntegers()");
        System.out.println(String.format("zero = %d \t one = %d", Zero.intValue(), One.intValue()));
        Integer Temp = new Integer(Zero);
        Zero = One;
        One = Temp;
        System.out.println("Without using a function to swap");
        System.out.println(String.format("zero = %d \t one = %d", Zero.intValue(), One.intValue()));
    }

    public static void swapPrimitives(int left, int right) {
        int temp = left;
        left = right;
        right = temp;
    }

    public static void swapIntegers(Integer left, Integer right) {
        Integer temp = new Integer(left);
        left = right;
        right = temp;
    }

    public static void swapAtomicIntegers(AtomicInteger left, AtomicInteger right) {
        left.set(right.getAndSet(left.get()));
    }


}