Java中的 LocalDate toEpochSecond() 方法及示例

LocalDate类的toEpochSecond()方法用于将此 LocalDate 转换为自 1970-01-01T00:00:00Z 纪元以来的秒数。该方法将此本地日期与作为参数传递的指定时间和偏移量相结合，以计算纪元秒值，即从 1970-01-01T00:00:00Z 开始经过的秒数。纪元之后时间线上的瞬间是正的，更早的是负的。

句法：

public long toEpochSecond(LocalTime time,
                          ZoneOffset offset)

参数：该方法接受两个参数时间和偏移量，分别是本地时间和区域偏移量。

返回值：此方法返回long ，即自1970-01-01T00:00:00Z epoch 以来的秒数，可能为负数。

下面的程序说明了 toEpochSecond() 方法：

方案一：

// Java program to demonstrate
// LocalDate.toEpochSecond() method
  
import java.time.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a LocalDate object
        LocalDate localD
            = LocalDate.parse("2018-12-06");
  
        // print LocalDate
        System.out.println("LocalDate: "
                           + localD);
  
        // create a LocalTime object
        LocalTime time
            = LocalTime.parse("20:12:32");
  
        // print Instant
        System.out.println("Passed LocalTime: "
                           + time);
  
        // create ZoneId
        ZoneOffset zone = ZoneOffset.of("Z");
  
        // print ZoneId
        System.out.println("Passed ZoneOffset: "
                           + zone);
  
        // print result
        System.out.println("Epoch Second: "
                           + localD.toEpochSecond(time, zone));
    }
}

输出：

LocalDate: 2018-12-06
Passed LocalTime: 20:12:32
Passed ZoneOffset: Z
Epoch Second: 1544127152

方案二：

// Java program to demonstrate
// LocalDate.toEpochSecond() method
  
import java.time.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a LocalDate object
        LocalDate localD
            = LocalDate.parse("2019-01-01");
  
        // print LocalDate
        System.out.println("LocalDate: "
                           + localD);
  
        // create a LocalTime object
        LocalTime time
            = LocalTime.parse("00:00:00");
  
        // print Instant
        System.out.println("Passed LocalTime: "
                           + time);
  
        // create ZoneId
        ZoneOffset zone = ZoneOffset.of("Z");
  
        // print ZoneId
        System.out.println("Passed ZoneOffset: "
                           + zone);
  
        // print result
        System.out.println("Epoch Second: "
                           + localD.toEpochSecond(time, zone));
    }
}

输出：

LocalDate: 2019-01-01
Passed LocalTime: 00:00
Passed ZoneOffset: Z
Epoch Second: 1546300800

参考： https://docs.oracle.com/javase/10/docs/api/java Java .time.LocalTime, Java Java)