package com.lyms.talkonlineweb.util;

import lombok.extern.slf4j.Slf4j;

import java.text.DateFormat;
import java.text.ParsePosition;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;

/**
 * @ProjectName: talkonline
 * @Package: com.lyms.talkonlineweb.util
 * @ClassName: DateUtil
 * @Author: lqy
 * @Description: 时间格式类
 * @Date: 2021-09-07 17:53
 * @Version:
 */
public class DateUtil {
    /**
     * 缓存时间格式化
     */
    private static ConcurrentHashMap<String, DateFormat> dateFormatCache = new ConcurrentHashMap<String, DateFormat>();
    private static Lock lock = new ReentrantLock();

    public static final String YYYY_MM_DD_HH_MM_SS = "yyyy-MM-dd HH:mm:ss";
    public static final String YYYY_MM_DD = "yyyy-MM-dd";
    /**
     * 私有构造方法，禁止对该类进行实例化
     */
    private DateUtil() {
    }

    public static String getYyyyMmDdHhMmSs(Date datetime) {
        return getDateTime(datetime, YYYY_MM_DD_HH_MM_SS);
    }

    public static String getDateTime(Date date, String pattern) {
        if (date == null) {
            return "";
        }

        DateFormat format = getDateFormat(pattern);
        lock.lock();
        try {
            return format.format(date);
        } finally {
            lock.unlock();
        }
    }

    public static DateFormat getDateFormat(String pattern) {
        if (StringUtil.isEmpty(pattern)) {
            pattern = YYYY_MM_DD;
        }

        if (dateFormatCache.get(pattern) != null) {
            return dateFormatCache.get(pattern);
        }
        lock.lock();
        try {
            DateFormat format = new SimpleDateFormat(pattern);
            dateFormatCache.put(pattern, format);
            return format;
        } catch (Exception e) {
        } finally {
            lock.unlock();
        }
        return null;
    }

    public static String getSeqString() {
        SimpleDateFormat fm = new SimpleDateFormat("yyMMddHHmmss");
        return fm.format(new Date());
    }

}