1.通过Util包中的Date获取

Date date = new Date(); 
SimpleDateFormat dateFormat= new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
System.out.println(dateFormat.format(date));

2.通过Util包的Calendar 获取

Calendar calendar= Calendar.getInstance(); 
SimpleDateFormat dateFormat= new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
System.out.println(dateFormat.format(calendar.getTime()));

3.通过Util包的Calendar 获取时间，分别获取年月日时分秒

Calendar cal=Calendar.getInstance();       
int y=cal.get(Calendar.YEAR);       
int m=cal.get(Calendar.MONTH);      
int d=cal.get(Calendar.DATE);       
int	h=cal.get(Calendar.HOUR_OF_DAY);       
int	mi=cal.get(Calendar.MINUTE);       
int s=cal.get(Calendar.SECOND);