import java.time.LocalDate;
import java.time.temporal.ChronoUnit;

LocalDate dateBefore =  LocalDate.of(2020, 05, 20);
LocalDate dateAfter = LocalDate.now();
    
long daysBetween =  ChronoUnit.DAYS.between(dateBefore, dateAfter);
long monthsBetween= ChronoUnit.MONTHS.between(dateBefore, dateAfter);
long yearsBetween= ChronoUnit.YEARS.between(dateBefore, dateAfter);
    
System.out.println(daysBetween);

如果你想要逻辑日历日，请使用java.time.temporal.ChronoUnit中的days .between()方法:

LocalDate dateBefore;
LocalDate dateAfter;
long daysBetween = DAYS.between(dateBefore, dateAfter);

如果你想要24小时的天，(一个duration)，你可以使用duration类:

LocalDate today = LocalDate.now()
LocalDate yesterday = today.minusDays(1);
// Duration oneDay = Duration.between(today, yesterday); // throws an exception
Duration.between(today.atStartOfDay(), yesterday.atStartOfDay()).toDays() // another option

更多信息请参考本文档。

根据VGR的评论，以下是你可以使用的方法:

ChronoUnit.DAYS.between(firstDate, secondDate)

DAYS.between

你可以使用DAYS。from java.time.temporal.ChronoUnit

e.g.

import java.time.temporal.ChronoUnit;
...

long totalDaysBetween(LocalDate dateBefore, LocalDate dateAfter) {
    return DAYS.between(dateBefore, dateAfter);

你可以使用until:

LocalDate independenceDay = LocalDate.of(2014, Month.JULY, 4);
LocalDate christmas = LocalDate.of(2014, Month.DECEMBER, 25);

System.out.println("Until christmas: " + independenceDay.until(christmas));
System.out.println("Until christmas (with crono): " + independenceDay.until(christmas, ChronoUnit.DAYS));

输出:

Until christmas: P5M21D
Until christmas (with crono): 174

如注释中所述，如果在返回Period之前没有指定单位。

文档片段:

ISO-8601日历系统中基于日期的时间量，例如“2年3个月4天”。 该类以年、月和日为单位对时间的数量或数量进行建模。有关该类的基于时间的等价物，请参见Duration。

使用枚举java.time.temporal.ChronoUnit中的DAYS。下面是示例代码:

输出: *开始日期:2015-03-01到结束日期:2016-03-03的天数为==> 368。 **开始日期:2016-03-03到结束日期:2015-03-01之间的天数==> -368*

package com.bitiknow.date;

import java.time.LocalDate;
import java.time.temporal.ChronoUnit;

/**
 * 
 * @author pradeep
 *
 */
public class LocalDateTimeTry {
    public static void main(String[] args) {

        // Date in String format.
        String dateString = "2015-03-01";

        // Converting date to Java8 Local date
        LocalDate startDate = LocalDate.parse(dateString);
        LocalDate endtDate = LocalDate.now();
        // Range = End date - Start date
        Long range = ChronoUnit.DAYS.between(startDate, endtDate);
        System.out.println("Number of days between the start date : " + dateString + " and end date : " + endtDate
                + " is  ==> " + range);

        range = ChronoUnit.DAYS.between(endtDate, startDate);
        System.out.println("Number of days between the start date : " + endtDate + " and end date : " + dateString
                + " is  ==> " + range);

    }

}