java-时间格式化 整5分钟，整10分钟

  public SimpleDateFormat df1 = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
  // time_str 为时间字符串 
  public String minute_fromt (String time_str,Integer is_gt) {
    // start_time is_gt 为 1 ; end_time is_gt为 0
    is_gt = is_gt*5;
    Calendar calendar = Calendar.getInstance();
    try {
        calendar.setTime(df1.parse(time_str));
    } catch (ParseException e) {
        e.printStackTrace();
    }
    int minute = calendar.get(Calendar.MINUTE);
    int sec = calendar.get(Calendar.SECOND);
    if (sec == 0) {
        is_gt = 0;
    }
    // 计算整10分钟 把5换成10
    minute = Math.round(minute/5*5);//计算5的整数分钟

    calendar.set(Calendar.MINUTE, minute+is_gt);
    calendar.set(Calendar.SECOND, 0);
    String time =df1.format(calendar.getTime());
    return time;

}
public String hour_fromt (String time_str,Integer is_gt) {
    // start_time is_gt 为 1 ; end_time is_gt为 0
    Calendar calendar = Calendar.getInstance();
    try {
        calendar.setTime(df1.parse(time_str));
    } catch (ParseException e) {
        e.printStackTrace();
    }
    int hour = calendarget(Calendar.HOUR);
    int minute = calendar.get(Calendar.MINUTE);
    int sec = calendar.get(Calendar.SECOND);

    if (sec == 0 && minute==0) {
        is_gt = 0;
    }
    calendar.set(Calendar.HOUR, hour+is_gt);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    String time =df1.format(calendar.getTime());
    return time;

}
public String day_fromt (String time_str,Integer is_gt) {
    // start_time is_gt 为 1 ; end_time is_gt为 0
    Calendar calendar = Calendar.getInstance();
    try {
        calendar.setTime(df1.parse(time_str));
    } catch (ParseException e) {
        e.printStackTrace();
    }
    int day = calendar.get(Calendar.DATE);
    int hour = calendar.get(Calendar.HOUR);
    int minute = calendar.get(Calendar.MINUTE);
    int sec = calendarget(Calendar.SECOND);

    if (sec == 0 && minute==0 && hour==0) {
        is_gt = 0;
    }
    calendar.set(Calendar.DATE, day+is_gt);
    calendar.set(Calendar.HOUR, 0);
    calendar.set(Calendar.MINUTE, 0);
    calendar.set(Calendar.SECOND, 0);
    String time =df1.format(calendar.getTime());
    return time;

}