Java获得当前时间

public class DateHandler {

 public static void main(String[] args) {
  DateHandler dh = new DateHandler();
  dh.getCurrentDateByDate();
  dh.getCurrentDateByCalendar();
 }

 // 使用Date类得到当前时间
 public void getCurrentDateByDate() {
  Date date = new Date();
  SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  String currentDate = sdf.format(date);
  System.out.println("当期时间:" + currentDate);
 }

 // 使用Calendar得到当前时间
 public void getCurrentDateByCalendar() {
  Calendar calendar = Calendar.getInstance();
  String currentDate = calendar.get(Calendar.YEAR) + "-"
    + (calendar.get(Calendar.MONTH) + 1) + "-"
    + calendar.get(Calendar.DAY_OF_MONTH) + " "
    + calendar.get(Calendar.HOUR_OF_DAY) + ":"
    + calendar.get(Calendar.MINUTE) + ":"
    + calendar.get(Calendar.SECOND);
  System.out.println("当期时间:" + currentDate);
 }
 
 public void getHour(){
  //12小时
  SimpleDateFormat sdf1 = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
  //24小时
  SimpleDateFormat sdf2 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  
  Calendar c = Calendar.getInstance();
  c.get(Calendar.HOUR);//12小时
  c.get(Calendar.HOUR_OF_DAY);//24小时
 }
}