1 public class test {
 2 
 3     public static void main(String[] args) {
 4         long ms = 300000;
 5         SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");//這裡想要只保留分秒可以寫成"mm:ss"
 6         formatter.setTimeZone(TimeZone.getTimeZone("GMT+00:00"));
 7         String hms = formatter.format(ms);
 
 8         System.out.println(hms);
 9     }
10 
11 }