public class ThisTest
{
    public static void main (String[] args)
    {
        SimpleTime time = new SimpleTime(15, 30, 19);
        System.out.println(time.buildString());
    }
}
class SimpleTime
{
    private int hour;
    private int minute;
    private int second;

    public SimpleTime(int hour, int minute, int second)
    {
        this.hour=hour;
        this.minute=minute;
        this.second=second;
    }

    public String buildString()
    {
        return String.format("%24s: %s\n%24s: %s",
            "this.toUniversalString()", this.toUniversalString(),
            "toUniversalString()", toUniversalString());
    }

    public String toUniversalString()
    {
        return String.format( "%02d:%02d:%02d",
            this.hour, this.minute, this.second);
    }
}