FastDateFormat日期工具类

原文：https://blog.csdn.net/u013823538/article/details/80197476

public class DateUtil {
    public static final FastDateFormat FORMAT_yyyyMMddHHmmss=FastDateFormat.getInstance("yyyy-MM-dd HH:mm:ss");
    public static final FastDateFormat FORMAT_yyyyMMdd=FastDateFormat.getInstance("yyyy-MM-dd");
    public static final FastDateFormat FORMAT_yyMMdd=FastDateFormat.getInstance("yy-MM-dd");
    public static final FastDateFormat FORMAT_HHmmss=FastDateFormat.getInstance("HH:mm:ss");
    /**
     * 最常用的格式化10位时间戳为yyyyMMddHHmmss
     * @return
     */
    public static String getNormalTime(String timestamp){
        return FORMAT_yyyyMMddHHmmss.format(getDate(timestamp));
    }
    /**
     * 获得10位时间戳
     * @param date
     * @return
     */
    public static String getTimestamp(Date date){
        return String.valueOf(date.getTime()/1000);
    }
    /**
     * 10位时间戳转日期
     * @param timestamp
     * @return
     */
    public static Date getDate(String timestamp){
        return new Date(Long.valueOf(timestamp+"000"));
    }
    /**
     * 获得本周开始时间
     * @return
     */
    public static Date getStartOfThisWeek() {
        Calendar calendar=Calendar.getInstance();
        calendar.setTime(new Date());
        calendar.setFirstDayOfWeek(Calendar.MONDAY);;
        calendar.set(Calendar.DAY_OF_WEEK, Calendar.MONDAY);
        calendar.set(Calendar.HOUR_OF_DAY, 0);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);
        calendar.set(Calendar.MILLISECOND,0);
        return calendar.getTime();
    }

    public static void main(String[] args) {
        getStartOfThisWeek();
    }
    /**
     * 获得本周开始时间
     * @return
     */
    public static String getStartOfThisWeekString() {
        return String.valueOf(getStartOfThisWeek().getTime()/1000);
    }
    /**
     * 获得本月开始时间
     * @return
     */
    public static Date getStartOfThisMonth() {
        Calendar calendar=Calendar.getInstance();
        calendar.setTime(new Date());
        calendar.set(Calendar.DAY_OF_MONTH, 1);
        calendar.set(Calendar.HOUR_OF_DAY, 0);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);
        return calendar.getTime();
    }
    /**
     * 获得本月开始时间
     * @return
     */
    public static String getStartOfThisMonthString() {
        return String.valueOf(getStartOfThisMonth().getTime()/1000);
    }
}