Roll the java.util.Time forward or backward in Java

/*from   w w  w  . j a v  a  2s . c  o m*/
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

public class Main {

  /**
   * Roll the java.util.Time forward or backward.
   * 
   * @param startDate
   *          - The start date
   * @period Calendar.YEAR etc
   * @param amount
   *          - Negative to rollbackwards.
   */
  public static java.sql.Time rollTime(java.util.Date startDate, int period,
      int amount) {
    GregorianCalendar gc = new GregorianCalendar();
    gc.setTime(startDate);
    gc.add(period, amount);
    return new java.sql.Time(gc.getTime().getTime());
  }

  public static void main(String[] argv) {
    System.out.println(rollTime(new Date(), Calendar.MINUTE, 10));
  }
}