java时间戳计算时间间隔

Java中可以使用`java.util.Date`和`java.time.LocalDateTime`类来计算时间间隔。

方法一：使用java.util.Date类

import java.util.Date;

public class TimeDiff {
    public static void main(String[] args) {
        Date startTime = new Date(1630368000000L); // 2021-08-31 00:00:00
        Date endTime = new Date(1630454400000L); // 2021-09-01 00:00:00

        long diffInMillies = Math.abs(endTime.getTime() - startTime.getTime());
        long diff = diffInMillies / (60 * 60 * 1000); // 计算小时数

        System.out.println("时间间隔为：" + diff + "小时");
    }
}

方法二：使用java.time.LocalDateTime类

import java.time.LocalDateTime;
import java.time.Duration;

public class TimeDiff {
    public static void main(String[] args) {
        LocalDateTime startTime = LocalDateTime.of(2021, 8, 31, 0, 0, 0);
        LocalDateTime endTime = LocalDateTime.of(2021, 9, 1, 0, 0, 0);

        Duration duration = Duration.between(startTime, endTime);
        long diff = Math.abs(duration.toHours()); // 计算小时数

        System.out.println("时间间隔为：" + diff + "小时");
    }
}