DateUtil

package com.huawei.it.gts.ls.utils;

import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.time.Instant;
import java.time.LocalDate;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZonedDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Calendar;
import java.util.Date;
import java.util.Locale;

/**
 * 时间工具类
 * @author z00438584
 */
public class DateUtil {

    public static final String DATE_TIME_FORMAT_DEFALUT = "yyyy/MM/dd HH:mm:ss";

    public static final String FULL_TIME_PATTERN = "yyyyMMddHHmmss";

    public static final String FULL_TIME_SPLIT_PATTERN = "yyyy-MM-dd HH:mm:ss";

    public static String formatFullTime(LocalDateTime localDateTime) {
        return formatFullTime(localDateTime, FULL_TIME_PATTERN);
    }

    public static String formatFullTime(LocalDateTime localDateTime, String pattern) {
        DateTimeFormatter dateTimeFormatter = DateTimeFormatter.ofPattern(pattern);
        return localDateTime.format(dateTimeFormatter);
    }

    private static String getDateFormat(Date date, String dateFormatType) {
        SimpleDateFormat simformat = new SimpleDateFormat(dateFormatType);
        return simformat.format(date);
    }

    public static String formatCSTTime(String date, String format) throws ParseException {
        SimpleDateFormat sdf = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy", Locale.US);
        Date d = sdf.parse(date);
        return DateUtil.getDateFormat(d, format);
    }

    public static int daysBetween(Date start, Date end) {
        Calendar calStart = Calendar.getInstance();
        Calendar calEnd = Calendar.getInstance();
        calStart.setTime(start);
        calEnd.setTime(end);
        // 设置时间为0时
        calStart.set(Calendar.HOUR_OF_DAY, 0);
        calStart.set(Calendar.MINUTE, 0);
        calStart.set(Calendar.SECOND, 0);
        calEnd.set(Calendar.HOUR_OF_DAY, 0);
        calEnd.set(Calendar.MINUTE, 0);
        calEnd.set(Calendar.SECOND, 0);
        // 得到相差的天数
        int days = ((int) (calEnd.getTime().getTime() / 1000) - (int) (calStart.getTime().getTime() / 1000)) / 3600 / 24;
        return days;
    }

    public static Date getDateAddDay(Date date, int days) {
        Calendar c = Calendar.getInstance();
        c.setTime(date);
        c.add(Calendar.DAY_OF_MONTH, days);
        return c.getTime();
    }

    public static String getDateStringByFormat(Date date, String dateFormat) {
        if (date == null) {
            return null;
        }
        SimpleDateFormat simpleDateFormat = new SimpleDateFormat(dateFormat);
        return simpleDateFormat.format(date);
    }

    public static int dateCompare(Date date1, Date date2) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyyMMdd");
        String dateFirst = dateFormat.format(date1);
        String dateLast = dateFormat.format(date2);
        int dateFirstIntVal = Integer.parseInt(dateFirst);
        int dateLastIntVal = Integer.parseInt(dateLast);
        if (dateFirstIntVal > dateLastIntVal) {
            return 1;
        } else if (dateFirstIntVal < dateLastIntVal) {
            return -1;
        }
        return 0;
    }

    /**
     * Date转成LocalDateTime，使用系统默认时区
     */
    public static LocalDateTime date2LocalDateTime(Date date){
        // An instantaneous point on the time-line.(时间线上的一个瞬时点。)
        Instant instant = date.toInstant();
        ZoneId zoneId = ZoneId.systemDefault();
        //A time-zone ID, such as {@code Europe/Paris}.(时区)
        LocalDateTime localDateTime = instant.atZone(zoneId).toLocalDateTime();
        return localDateTime;
    }

    /**
     * LocalDateTime转成Date，使用系统默认时区
     */
    public static Date localDateTime2Date( LocalDateTime localDateTime){
        ZoneId zoneId = ZoneId.systemDefault();
        // Combines this date-time with a time-zone to create a  ZonedDateTime.
        ZonedDateTime zdt = localDateTime.atZone(zoneId);
        Date date = Date.from(zdt.toInstant());
        return date;
    }

    /** LocalDateTime转成String */
    public static String localDateTime2Str(LocalDateTime localDateTime, String formatStr) {
        DateTimeFormatter df = DateTimeFormatter.ofPattern(formatStr);
        String localDateTimeStr = df.format(localDateTime);
        return localDateTimeStr;
    }

    /** LocalDateTime转成String,默认格式：yyyy/MM/dd HH:mm:ss */
    public static String localDateTime2Str(LocalDateTime localDateTime) {
        return localDateTime2Str(localDateTime, DATE_TIME_FORMAT_DEFALUT);
    }

    /**
     * 日期时间字符串转LocalDateTime
     * @author xWX787141
     * @param dateTime 时间字符串
     * @param format 时间字符串格式，必须带时分秒
     * @return
     */
    public static LocalDateTime string2DateTime(String dateTime,String format) {
        DateTimeFormatter df = DateTimeFormatter.ofPattern(format);
        return LocalDateTime.parse(dateTime,df);
    }

    /**
     * 日期时间字符串转LocalDate
     * @author xWX787141
     * @param date 时间字符串
     * @param format 时间字符串格式，不带时分秒
     * @return
     */
    public static LocalDate string2Date(String date,String format) {
        DateTimeFormatter df = DateTimeFormatter.ofPattern(format);
        return LocalDate.parse(date,df);
    }

}