在本文中，您将找到几种在 Java 中为日期添加或减去年、月、日、小时、分钟或秒的方法。

使用Calendar类添加/减去年、月、日、小时、分钟、秒到日期

import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;

public class CalendarAddSubtractExample {
    public static void main(String[] args) {
        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        Date date = new Date();
        System.out.println("Current Date " + dateFormat.format(date));

        // Convert Date to Calendar
        Calendar c = Calendar.getInstance();
        c.setTime(date);

        // Perform addition/subtraction
        c.add(Calendar.YEAR, 2);
        c.add(Calendar.MONTH, 1);
        c.add(Calendar.DATE, -10);
        c.add(Calendar.HOUR, -4);
        c.add(Calendar.MINUTE, 30);
        c.add(Calendar.SECOND, 50);

        // Convert calendar back to Date
        Date currentDatePlusOne = c.getTime();

        System.out.println("Updated Date " + dateFormat.format(currentDatePlusOne));
    }
}

# Output
Current Date 2020-02-24 19:35:00
Updated Date 2022-03-14 16:05:50

向 LocalDateTime 添加/减去年、月、周、日、小时、分钟、秒

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

public class LocalDateTimeAddSubtractExample {
    public static void main(String[] args) {
        LocalDateTime dateTime = LocalDateTime.of(2020, 1, 26, 10, 30, 45);

        // Add years, months, weeks, days, hours, minutes, seconds to LocalDateTime
        LocalDateTime newDateTime = dateTime.plusYears(3).plusMonths(1).plusWeeks(4).plusDays(2).plusHours(2);
        System.out.println(newDateTime);


        // Subtract years, months, weeks, days, hours, minutes, seconds to LocalDateTime
        newDateTime = dateTime.minusYears(3).minusMonths(1).minusWeeks(4).minusDays(2).minusMinutes(30);
        System.out.println(newDateTime);

        // Add/Subtract using the generic plus/minus method
        System.out.println(dateTime.plus(2, ChronoUnit.DAYS));

    }
}

# Output
2023-03-28T12:30:45
2016-11-26T10:00:45
2020-01-28T10:30:45

在 LocalDate 中添加/减去天、周、月、年

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

public class LocalDateAddSubtractExample {
    public static void main(String[] args) {
        LocalDate date = LocalDate.of(2020, 1, 26);

        // Add years, months, weeks, days to LocalDate
        LocalDate newDate = date.plusYears(3).plusMonths(1).plusWeeks(4).plusDays(2);
        System.out.println(newDate);


        // Subtract years, months, weeks, days to LocalDate
        newDate = date.minusYears(3).minusMonths(1).minusWeeks(4).minusDays(2);
        System.out.println(newDate);

        // Add/Subtract using the generic plus/minus method
        System.out.println(date.plus(2, ChronoUnit.DAYS));

    }
}

2023-03-28
2016-11-26
2020-01-28

向LocalDate添加/减去小时、分钟、秒

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

public class LocalTimeAddSubtractExample {
    public static void main(String[] args) {
        LocalTime time = LocalTime.of(11, 45, 20);

        // Add hours, minutes, or seconds
        LocalTime newTime = time.plusHours(2).plusMinutes(30).plusSeconds(80);
        System.out.println(newTime);

        // Subtract hours, minutes, or seconds
        LocalTime updatedTime = time.minusHours(2).minusMinutes(30).minusSeconds(30);
        System.out.println(updatedTime);

        // Add/Subtract using the generic plus/minus method
        System.out.println(time.plus(1, ChronoUnit.HOURS));

    }
}

# Output
14:16:40
09:14:50
12:45:20