How to print out the contents of the list on a single line

<pre>public class WrapperExample
{
    private Scanner scanner;
    private ArrayList<Integer> numbers;

    /**
     * Constructor for objects of class WrapperExample.
     */
    public WrapperExample()
    {
        scanner = new Scanner(System.in);
        numbers = new ArrayList<>();
    }

    /**
     * Read integer from standard input (System.in)
     * and store them in the list. The end of the
     * input is indicated by a negative integer.
     * The negative integer must not be stored in the list.
     */
    public void readNumbers()
    {
        int i = scanner.nextInt();
        // Get rid of any previous numbers.
        numbers.clear();
        // Read a fresh set of integers ...
        while (i >= 0){
            numbers.add(i);
            i = scanner.nextInt();
        }
    }

    /**
     * Print out the integers in the numbers list.
     * Print the numbers on a single line, with a single space
     * between each.
     */
    public void printNumbers()
    {
        // Print out the numbers.

        // Terminate the line.
        for(Integer interger: numbers){
            System.out.println(scanner.nextInt());
        }

    }   
}