日期工具类，获取今天明天，最近七天，每月，每年第一天和最后一天的日期

/**
 * 日期工具类
 */
public class DateUtils2 {

    /**
     * 获取今天
     *
     * @return String
     */
    public static String getToday() {
        return new SimpleDateFormat("yyyy-MM-dd").format(new Date());
    }

    /**
     * 获取昨天
     *
     * @return String
     */
    public static String getYestoday() {
        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.DATE, -1);
        Date time = cal.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(time);
    }


    /**
     * 获取本月开始日期
     *
     * @return String
     **/
    public static String getMonthStart() {
        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.MONTH, 0);
        cal.set(Calendar.DAY_OF_MONTH, 1);
        Date time = cal.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(time) + " 00:00:00";
    }
    /** 
    * @Description: 得到七天的日期，包括今天
    * @return: java.util.List<java.lang.String>
    */
    public static List<String> getSevenDate() {

        List<String> dateList = new ArrayList<>();
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");

        for (int i = 0; i < 7; i++) {

            Date date = DateUtils.addDays(new Date(), -i);
            String formatDate = sdf.format(date);
            dateList.add(formatDate);
        }
        return dateList;
    }
    /**
     * 获取本月最后一天
     *
     * @return String
     **/
    public static String getMonthEnd() {
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.DAY_OF_MONTH, cal.getActualMaximum(Calendar.DAY_OF_MONTH));
        Date time = cal.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(time) + " 23:59:59";
    }

    /**
     * 获取本周的第一天
     *
     * @return String
     **/
    public static String getWeekStart() {
        Calendar cal = Calendar.getInstance();
        cal.add(Calendar.WEEK_OF_MONTH, 0);
        cal.set(Calendar.DAY_OF_WEEK, 2);
        Date time = cal.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(time) + " 00:00:00";
    }

    /**
     * 获取本周的最后一天
     *
     * @return String
     **/
    public static String getWeekEnd() {
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.DAY_OF_WEEK, cal.getActualMaximum(Calendar.DAY_OF_WEEK));
        cal.add(Calendar.DAY_OF_WEEK, 1);
        Date time = cal.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(time) + " 23:59:59";
    }

    /**
     * 获取本年的第一天
     *
     * @return String
     **/
    public static String getYearStart() {
        return new SimpleDateFormat("yyyy").format(new Date()) + "-01-01 00:00:00";
    }

    /**
     * 获取本年的最后一天
     *
     * @return String
     **/
    public static String getYearEnd() {
        Calendar calendar = Calendar.getInstance();
        calendar.set(Calendar.MONTH, calendar.getActualMaximum(Calendar.MONTH));
        calendar.set(Calendar.DAY_OF_MONTH, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
        Date currYearLast = calendar.getTime();
        return new SimpleDateFormat("yyyy-MM-dd").format(currYearLast) + " 23:59:59";
    }

       /*获取前一个小时*/
    public static String getLastHour() {
        //getInstance()将返回一个Calendar的对象。
        Calendar calendar = Calendar.getInstance();
        //设置小时
        calendar.set(Calendar.HOUR_OF_DAY, calendar.get(Calendar.HOUR_OF_DAY) - 1);
        //格式化时间
        SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd HH");
        //打印出时间
        System.out.println("一个小时前的时间：" + df.format(calendar.getTime()));
        System.out.println("当前的时间：" + df.format(new Date()));
        return df.format(calendar.getTime());
    }




    public static void main(String[] args) {
        System.out.println("获取今天:" + getToday());
        System.out.println("获取昨天:" + getYestoday());
        System.out.println("获取最近七天:" + getSevenDate);
        System.out.println("获取本月开始日期:" + getMonthStart());
        System.out.println("获取本月最后一天:" + getMonthEnd());
        System.out.println("获取本周的第一天:" + getWeekStart());
        System.out.println("获取本周的最后一天:" + getWeekEnd());
        System.out.println("获取本年的第一天:" + getYearStart());
        System.out.println("获取本年的最后一天:" + getYearEnd());
        System.out.println("获取前一个小时:" + getLastHour());
    }

}

获取最近七天的方法需要加入一个依赖

 <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>