DateUtils

package com.shebao.dispatch.common.utils;

import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.DateUtil;

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.time.*;
import java.time.format.DateTimeFormatter;
import java.util.*;

/**
 * 日期工具
 *
 */
public class DateUtils extends org.apache.commons.lang3.time.DateUtils{

    public static final String TL_DF_DATE = "yyyy-MM-dd";
    public static final String TL_DF_DATETIME = "yyyy-MM-dd HH:mm:ss";
    public static final String TL_DF_UTC = "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'";
    public static final String TL_DF_YYYY_DATETIME = "yyyyMMddHHmmss";

    private static String[] parsePatterns = {"yyyy-MM-dd", "yyyy-MM-dd HH:mm:ss",
            "yyyy-MM-dd HH:mm", "yyyy-MM-dd HH", "yyyy-MM", "yyyy/MM/dd", "yyyy/MM/dd HH:mm:ss",
            "yyyy/MM/dd HH:mm", "yyyy/MM/dd HH", "yyyy/MM", "yyyy.MM.dd", "yyyy.MM.dd HH:mm:ss",
            "yyyy.MM.dd HH:mm", "yyyy.MM.dd HH", "yyyy.MM", "yyyy年MM月dd日", "yyyy年MM月dd日 HH时mm分ss秒",
            "yyyy年MM月dd日 HH时mm分", "yyyy年MM月dd日 HH时", "yyyy年MM月", "yyyy"};

    private static Set<String> DATEFORMAT_SET = new LinkedHashSet<>();
    static {
    	DATEFORMAT_SET.add(TL_DF_DATE);
    	DATEFORMAT_SET.add(TL_DF_DATETIME);
    	DATEFORMAT_SET.add("yyyy/MM/dd");
    	DATEFORMAT_SET.add("yyyy/MM/dd HH:mm:ss");
    	DATEFORMAT_SET.add("yyyyMMdd");
    	DATEFORMAT_SET.add("yyyyMMdd HH:mm:ss");
    	DATEFORMAT_SET.add(TL_DF_YYYY_DATETIME);
    	DATEFORMAT_SET.add(TL_DF_UTC);
    }

    public static Date parseDateCommon(Object str) {
        if (str == null) {
            return null;
        }
        if ((str.toString().matches("^[0-9]*$")) && str.toString().length() > 4) {
            return new Date(Long.parseLong(str.toString()));
        }
        try {
            return parseDate(str.toString(), parsePatterns);
        } catch (ParseException e) {
            return null;
        }
    }

    /**
     * @return 当前时间戳, 秒级
     */
    public static int currentTimeInSeconds() {
        return (int) (System.currentTimeMillis()/1000);
    }
    public static String formateToDateTimeNo(Date date){
        return formatNullable(date, TL_DF_YYYY_DATETIME);
    }
    public static String formatTo(Date date, String fmt) {
        return formatNullable(date, fmt);
    }
    public static String formatToDate(Date date) {
        return formatNullable(date, TL_DF_DATE);
    }
    public static String formatToDatetime(Date date) {
        return formatNullable(date, TL_DF_DATETIME);
    }

    public static String formatToYmdDate(Date date) {
        return formatNullable(date, TL_DF_DATE);
    }

    private static final DateTimeFormatter DATE_TIME_FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss");
    private static final DateTimeFormatter DATE_FORMATTER = DateTimeFormatter.ofPattern("yyyy-MM-dd");

    public static String currentAsDatetime() {
        return DATE_TIME_FORMATTER.format(LocalDateTime.now());
    }

    /**
     * 根据秒级时间戳获取Date对象
     * @param timestampInSeconds
     * @return
     */
    public static Date fromSeconds(Integer timestampInSeconds) {
        if(timestampInSeconds == null || timestampInSeconds < 0) {
            return new Date(Long.MAX_VALUE);
        }
        return new Date(timestampInSeconds.longValue() * 1000);
    }

    static Date getDateFromUtcString(String str) {
        try {
            return getDateFormat(TL_DF_UTC).parse(str);
        } catch (ParseException e) {
            return null;
        }
    }

    /**
     * 获取当天起始时间
     * @return
     */
    public static Long getDayStartTime(String params) {
        if (StringUtils.isEmpty(params)) {
            return null;
        }
        Date date = parseDate(params);
        if (date != null) {
            LocalDate localDate = date.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
            return LocalDateTime.of(localDate, LocalTime.MIN).toInstant(ZoneOffset.of("+8")).getEpochSecond();
        }
        return null;
    }

    /**
     * 获取当天结束时间
     * @return
     */
    public static Long getDayEndTime(String params) {
        if (StringUtils.isEmpty(params)) {
            return null;
        }
        Date date = parseDate(params);
        if (date != null) {
            LocalDate localDate = date.toInstant().atZone(ZoneId.systemDefault()).toLocalDate();
            return LocalDateTime.of(localDate, LocalTime.MAX).toInstant(ZoneOffset.of("+8")).getEpochSecond();
        }
        return null;
    }

    /**
     * 获取本月第一天
     * @return
     */
    public static Date getCurrentMonthFirstDay(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.setTime(date);
        calendar.set(Calendar.HOUR_OF_DAY, 0);
        calendar.set(Calendar.MINUTE, 0);
        calendar.set(Calendar.SECOND, 0);
        calendar.set(Calendar.MILLISECOND, 0);
        calendar.set(Calendar.DAY_OF_MONTH,1);
        return calendar.getTime();
    }

    /**
     * 获取上月最后天
     * @return
     */
    public static Date getPreviousMonthLastDay(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.clear();
        calendar.setTime(date);
        calendar.add(Calendar.MONTH,-1);
        calendar.set(Calendar.DAY_OF_MONTH,calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
        return calendar.getTime();
    }

    /**
     * 获取当前月最后天
     * @return
     */
    public static Date getCurrentMonthLastDay(Date date) {
        Calendar calendar = Calendar.getInstance();
        calendar.clear();
        calendar.setTime(date);
        calendar.set(Calendar.DAY_OF_MONTH,calendar.getActualMaximum(Calendar.DAY_OF_MONTH));
        return calendar.getTime();
    }



    /**
     * 将date对象转换为秒级时间戳
     * @param date
     * @return
     */
    public static int getTimeInSeconds(Date date) {
        if (date == null) {
            return 0;
        }
        return (int) (date.getTime() / 1000);
    }

    public static Date parseDate(String date) {
        try {
            return getDateFormat(TL_DF_DATE).parse(date);
        } catch (ParseException e) {
            return null;
        }
    }

    /**
     * 从 yyyy/MM/dd 中提取时间
     * @param date
     * @return
     */
    public static Date parseDate(String date, String fmt) {
        try {
            return getDateFormat(fmt).parse(date);
        } catch (ParseException e) {
            return null;
        }
    }

    public static Date parseDatetime(String date) {
        try {
            return getDateFormat(TL_DF_DATETIME).parse(date);
        } catch (ParseException e) {
            return null;
        }
    }

    /**
     * 尝试用各种方式从字符串识别时间
     * @param str 日期字符串
     * @return 识别成功返回date对象, 失败返回null
     */
    public static Date tryParseDate(String str) {
        if(StringUtils.isBlank(str)) {
            return null;
        }
        // 尝试以各种格式获取
        Date date;
        for (String fmt : DATEFORMAT_SET) {
            date = parseDate(str, fmt);
            if(date != null) {
                return date;
            }
        }
        // 尝试按excel时间戳获取
        try {
            double num = Double.parseDouble(str);
            if(DateUtil.isValidExcelDate(Double.valueOf(str))) {
                return DateUtil.getJavaDate(num);
            }
        } catch (NumberFormatException ignored) {
        }
        return null;
    }

    /**
     * 按格式返回date的格式化字符串, date为null 返回空字符串
     * @param date
     * @param fmt
     * @return
     */
    private static String formatNullable(Date date, String fmt) {
        DateFormat formatter = getDateFormat(fmt);
        if(date == null || date.getTime() == 0) {
            return "";
        }
        return formatter.format(date);
    }

    /**
     * 返回对应的DateFormat对象
     * @param fmt
     * @return
     */
    private static DateFormat getDateFormat(String fmt) {
        return new SimpleDateFormat(fmt);
    }

    /**
     * 计算两个日期月份差
     * @param sourceStart 开始日期
     * @param sourceEnd 截止日期
     * @return 差值
     */
    public static int calcMonthDifference(Date sourceStart, Date sourceEnd) {
        Calendar start = Calendar.getInstance();
        Calendar end = Calendar.getInstance();
        start.setTime(sourceStart);
        end.setTime(sourceEnd);
        int result = end.get(Calendar.MONTH) - start.get(Calendar.MONTH);
        int month = (end.get(Calendar.YEAR) - start.get(Calendar.YEAR)) * 12;
        return month + result;
    }

    /**
     * 计算两个日期天数差
     * @param sourceStart 开始日期
     * @param sourceEnd 截止日期
     * @return 差值
     */
    public static long getDayDifference(Date sourceStart, Date sourceEnd) {
        long dif = sourceEnd.getTime() - sourceStart.getTime();
        long day= dif /(24*60*60*1000);
        return day;
    }

    public static Date getDateAddDayDifference(Date source, int day) {
        Calendar c = Calendar.getInstance();
        c.setTime(source);
        c.add(Calendar.DAY_OF_MONTH, day);// 今天+1天
        Date dif = c.getTime();
        return dif;
    }

    /** 锁对象 */
    private static final Object lockObj = new Object();

    /** 存放不同的日期模板格式的sdf的Map */
    private static Map<String, ThreadLocal<SimpleDateFormat>> sdfMap = new HashMap<String, ThreadLocal<SimpleDateFormat>>();
    public static final String YYYY_MM = "yyyy-MM";
    public static final String YYYY_MM_CHINESE = "yyyy年MM月";

    /**
     * ron
     * 解决SimpleDateFormat静态化的坑
     * 返回一个ThreadLocal的sdf,每个线程只会new一次sdf
     * @param pattern
     * @return
     */
    private static SimpleDateFormat getSimpleDateFormat(final String pattern) {
        ThreadLocal<SimpleDateFormat> tl = sdfMap.get(pattern);
        // 双检锁是防止sdfMap这个单例被多次put重复的sdf
        if (tl == null) {
            synchronized (lockObj) {
                tl = sdfMap.get(pattern);
                if (tl == null) {

                    // 使用ThreadLocal<SimpleDateFormat>替代原来直接new SimpleDateFormat
                    tl = new ThreadLocal<SimpleDateFormat>() {

                        @Override
                        protected SimpleDateFormat initialValue() {
                            System.out.println("thread: " + Thread.currentThread() + " init pattern: " + pattern);
                            return new SimpleDateFormat(pattern);
                        }
                    };
                    // 只有Map中还没有这个pattern的sdf才会生成新的sdf并放入map
                    sdfMap.put(pattern, tl);
                }
            }
        }
        return tl.get();
    }

    /**
     * 获取当前日期
     *
     * @param pattern 日期格式，如：yyyy-MM-dd HH:mm:ss
     * @return
     */
    public static String getDateStr(String pattern) {
        String date = getSimpleDateFormat(pattern).format(new Date(System.currentTimeMillis()));
        return date;
    }


    public static Calendar getTime() {
        Calendar time=Calendar.getInstance();
        return time;
    }

    public static Calendar getTime(long timeMillis) {
        Calendar time=getTime();
        time.setTimeInMillis(timeMillis);
        return time;
    }
    public static Date getDate() {
        return getTime().getTime();
    }
    public static Date getDate(long timeMillis) {
        return getTime(timeMillis).getTime();
    }


    public static String getYYYYMMDD() {
        return getSimpleDateFormat("yyyyMMdd").format(getDate());
    }
    public static String getYYYYMMDD(long time) {
        return getSimpleDateFormat("yyyyMMdd").format(getDate(time));
    }
    public static String getYYYYMMDD(Date date) {
        return null==date ? "" : getSimpleDateFormat(TL_DF_DATE).format(date);
    }
    public static String getYYYYMMDDNullRetrunNoTimeLimit(Date date) {
        return null==date ? "无期限" : getSimpleDateFormat(TL_DF_DATE).format(date);
    }
    public static String getHHmmss() {
        return getSimpleDateFormat("HHmmss").format(getDate());
    }
    public static String getYYYYMMDDHHmmss(Date date) {
        return getSimpleDateFormat("yyyy-MM-dd HH:mm:ss").format(date);
    }
    public static String getYYYYMM() {
        return getSimpleDateFormat("yyyyMM").format(getDate());
    }
    public static String getYYYYMM(Date date) {
        if(date == null) {
            return null;
        }
        SimpleDateFormat YYYY_MM_FORMAT = new SimpleDateFormat(YYYY_MM);
        return YYYY_MM_FORMAT.format(date);
    }
    public static String getYYYYMMWithChinese(Date date) {
        if(date == null) {
            return "";
        }
        SimpleDateFormat YYYY_MM_FORMAT = new SimpleDateFormat(YYYY_MM_CHINESE);
        return YYYY_MM_FORMAT.format(date);
    }
    public static String getYYYYMM(long timeMillis) {
        return getSimpleDateFormat("yyyyMM").format(getDate(timeMillis));
    }
    public static String getMMDD() {
        return getSimpleDateFormat("MMdd").format(getTime());
    }
    public static String getMMDD(long timeMillis) {
        return getSimpleDateFormat("MMdd").format(getDate(timeMillis));
    }
    public static String getDD(long timeMillis) {
        return getSimpleDateFormat("dd").format(getDate(timeMillis));
    }

}