日期与字符串的转换

  Date now = new Date(System.currentTimeMillis());
  
  String s = "1985-2-14 1:2:0";
  Timestamp t = Timestamp.valueOf(s);
  System.out.println(t);
  System.out.println(t.toString());
  
  DateFormat df = DateFormat.getDateInstance(DateFormat.LONG);
  System.out.println();
  System.out.println(df.parse("1985年2月14日"));
  System.out.println(df.format(now));
  
  SimpleDateFormat sdf = new SimpleDateFormat("yyyy_MM_dd");
  System.out.println();
  System.out.println(sdf.parse("1985_2_14"));  
  System.out.println(sdf.format(now));
  
  Calendar c = Calendar.getInstance();
  c.setTime(now);
  System.out.println();
  System.out.println(c.get(Calendar.AM_PM) == Calendar.AM);
  System.out.println(c.get(Calendar.MONTH + 1));