1.timestamp 转 Calendar

    /**
     * timestamp 转 Calendar
     * @param timestamp
     * @return
     */
    public static Calendar timestampToCalendar(Timestamp timestamp) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(new Date(timestamp.getTime()));
        return calendar;
    }

2.timestamp 转Date

   /**
     * timestamp 转Date
     * @param timestamp
     * @return
     */
    public static Date timestampToDate(Timestamp timestamp) {
        return new Date(timestamp.getTime());
    }

3.calendar转Timestamp

  /**
     * calendar转Timestamp
     *
     * @param calendar
     * @return
     */
    public static Timestamp calendarToTimestamp(Calendar calendar) {
        return new Timestamp(calendar.getTimeInMillis());
    }