日期（date util）工具类

import java.lang.management.ManagementFactory;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.lang3.time.DateFormatUtils;

/**
 * 时间工具类
 * 
 * @author Ajie
 */
public class DateUtils extends org.apache.commons.lang3.time.DateUtils
{
    public static String YYYY = "yyyy";

    public static String YYYY_MM = "yyyy-MM";

    public static String YYYY_MM_DD = "yyyy-MM-dd";

    public static String YYYYMMDDHHMMSS = "yyyyMMddHHmmss";

    public static String YYYY_MM_DD_HH_MM_SS = "yyyy-MM-dd HH:mm:ss";
    
    private static String[] parsePatterns = {
            "yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss", "yyyy-MM-dd HH:mm", "yyyy-MM", 
            "yyyy/MM/dd", "yyyy/MM/dd HH:mm:ss", "yyyy/MM/dd HH:mm", "yyyy/MM",
            "yyyy.MM.dd", "yyyy.MM.dd HH:mm:ss", "yyyy.MM.dd HH:mm", "yyyy.MM"};

    /**
     * 获取当前Date型日期
     * 
     * @return Date() 当前日期
     */
    public static Date getNowDate()
    {
        return new Date();
    }

    /**
     * 获取当前日期, 默认格式为yyyy-MM-dd
     * 
     * @return String
     */
    public static String getDate()
    {
        return dateTimeNow(YYYY_MM_DD);
    }

    public static final String getTime()
    {
        return dateTimeNow(YYYY_MM_DD_HH_MM_SS);
    }

    public static final String dateTimeNow()
    {
        return dateTimeNow(YYYYMMDDHHMMSS);
    }

    public static final String dateTimeNow(final String format)
    {
        return parseDateToStr(format, new Date());
    }

    public static final String dateTime(final Date date)
    {
        return parseDateToStr(YYYY_MM_DD, date);
    }

    public static final String parseDateToStr(final String format, final Date date)
    {
        return new SimpleDateFormat(format).format(date);
    }

    public static final Date dateTime(final String format, final String ts)
    {
        try
        {
            return new SimpleDateFormat(format).parse(ts);
        }
        catch (ParseException e)
        {
            throw new RuntimeException(e);
        }
    }

    /**
     * 日期路径 即年/月/日 如2018/08/08
     */
    public static final String datePath()
    {
        Date now = new Date();
        return DateFormatUtils.format(now, "yyyy/MM/dd");
    }

    /**
     * 日期路径 即年/月/日 如20180808
     */
    public static final String dateTime()
    {
        Date now = new Date();
        return DateFormatUtils.format(now, "yyyyMMdd");
    }

    /**
     * 日期型字符串转化为日期 格式
     */
    public static Date parseDate(Object str)
    {
        if (str == null)
        {
            return null;
        }
        try
        {
            return parseDate(str.toString(), parsePatterns);
        }
        catch (ParseException e)
        {
            return null;
        }
    }
    
    /**
     * 获取服务器启动时间
     */
    public static Date getServerStartDate()
    {
        long time = ManagementFactory.getRuntimeMXBean().getStartTime();
        return new Date(time);
    }

    /**
     * 计算两个时间差
     */
    public static String getDatePoor(Date endDate, Date nowDate)
    {
        long nd = 1000 * 24 * 60 * 60;
        long nh = 1000 * 60 * 60;
        long nm = 1000 * 60;
        // long ns = 1000;
        // 获得两个时间的毫秒时间差异
        long diff = endDate.getTime() - nowDate.getTime();
        // 计算差多少天
        long day = diff / nd;
        // 计算差多少小时
        long hour = diff % nd / nh;
        // 计算差多少分钟
        long min = diff % nd % nh / nm;
        // 计算差多少秒//输出结果
        // long sec = diff % nd % nh % nm / ns;
        return day + "天" + hour + "小时" + min + "分钟";
    }


  /**
     * 判断日期格式:yyyy-mm-dd
     *
     * @param sDate
     * @return
     */
    public static boolean isValidDate(String sDate) {
        String datePattern1 = "\\d{4}-\\d{2}-\\d{2}";
        String datePattern2 = "^((\\d{2}(([02468][048])|([13579][26]))"
                + "[\\-\\/\\s]?((((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|"
                + "(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?"
                + "((0?[1-9])|([1-2][0-9])))))|(\\d{2}(([02468][1235679])|([13579][01345789]))[\\-\\/\\s]?("
                + "(((0?[13578])|(1[02]))[\\-\\/\\s]?((0?[1-9])|([1-2][0-9])|(3[01])))|(((0?[469])|(11))[\\-\\/\\s]?"
                + "((0?[1-9])|([1-2][0-9])|(30)))|(0?2[\\-\\/\\s]?((0?[1-9])|(1[0-9])|(2[0-8]))))))";
        if ((sDate != null)) {
            Pattern pattern = Pattern.compile(datePattern1);
            Matcher match = pattern.matcher(sDate);
            if (match.matches()) {
                pattern = Pattern.compile(datePattern2);
                match = pattern.matcher(sDate);
                return match.matches();
            } else {
                return false;
            }
        }
        return false;
    }
       /**
     * String转Date
     * @param date 日期
     * @param fmtString 格式化字符串(如：yyy-MM-dd)
     * @return
     */
    private static Date StringToDate(String date, String fmtString) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat(fmtString);
        return sdf.parse(date);
    }

    /**
     * 日期格式化
     * @param date 日期
     * @param fmtString 格式化字符串
     * @return
     */
    private static String FormatDate(Date date, String fmtString) {
        SimpleDateFormat sdf = new SimpleDateFormat(fmtString);
        return sdf.format(date);
    }

    /**
     * 日期格式化
     * @param date 日期
     * @return
     */
    public static Date StringToDate(String date) throws ParseException {
        return StringToDate(date, "yyyy-MM-dd");
    }

    public static Date StringToDate1(String date) throws ParseException {
        return StringToDate(date, "yyyy-MM-dd HH:mm");
    }

    public static String FormatDate(Date date) {
        return FormatDate(date, "yyyy-MM-dd");
    }

    public static String FormatDate1(Date date) {
        return FormatDate(date, "yyyy-MM-dd HH:mm");
    }

    /**
     * 根据生日计算当前周岁数
     */
    public static Integer getCurrentAge(Date birthday) {
        // 当前时间
        Calendar curr = Calendar.getInstance();
        // 生日
        Calendar born = Calendar.getInstance();
        born.setTime(birthday);
        // 年龄 = 当前年 - 出生年
        int age = curr.get(Calendar.YEAR) - born.get(Calendar.YEAR);
        if (age <= 0) {
            return 0;
        }
        // 如果当前月份小于出生月份: age-1
        // 如果当前月份等于出生月份, 且当前日小于出生日: age-1
        int currMonth = curr.get(Calendar.MONTH);
        int currDay = curr.get(Calendar.DAY_OF_MONTH);
        int bornMonth = born.get(Calendar.MONTH);
        int bornDay = born.get(Calendar.DAY_OF_MONTH);
        if ((currMonth < bornMonth) || (currMonth == bornMonth && currDay <= bornDay)) {
            age--;
        }
        return age < 0 ? 0 : age;
    }
   }