Java ZonedDateTime withEarlierOffsetAtOverlap()方法及示例

ZonedDateTime 类的 withEarlierOffsetAtOverlap() 方法用于在将区域偏移量改为本地时间线重叠处的两个有效偏移量中较早的一个后，返回该ZonedDateTime对象的副本。重叠发生在夏令时结束时，一个小时被返回到时间线。由于这个原因，本地日期时间有两个有效的偏移量，调用withEarlierOffsetAtOverlap方法将返回一个具有两个区域中较早的ZonedDateTime。如果在不是重叠的时候调用这个方法，就会返回这个。这个实例是不可改变的，不受这个方法调用的影响。

语法

public ZonedDateTime withEarlierOffsetAtOverlap()

参数： 该方法不接受任何参数。

返回值： 该方法返回一个基于该日期时间的 ZonedDateTime ，并带有较早的偏移。

下面的程序说明了withEarlierOffsetAtOverlap()方法。

程序1 :

// Java program to demonstrate
// withEarlierOffsetAtOverlap() method
  
import java.time.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a ZonedDateTime object
        ZonedDateTime zonedDT
            = ZonedDateTime
                  .ofLocal(
                      LocalDateTime.of(2018, 11, 4, 1, 25, 43),
                      ZoneId.of("US/Central"),
                      ZoneOffset.ofHours(-6));
  
        // print ZonedDateTime
        System.out.println("Before"
                           + " withEarlierOffsetAtOverlap():\n "
                           + zonedDT);
  
        // apply withEarlierOffsetAtOverlap()
        ZonedDateTime zonedDT2
            = zonedDT.withEarlierOffsetAtOverlap();
  
        // print ZonedDateTime after
        // withEarlierOffsetAtOverlap()
        System.out.println("\nAfter"
                           + " withEarlierOffsetAtOverlap():\n "
                           + zonedDT2);
    }
}

输出。

Before withEarlierOffsetAtOverlap():
 2018-11-04T01:25:43-06:00[US/Central]

After withEarlierOffsetAtOverlap():
 2018-11-04T01:25:43-05:00[US/Central]

程序2

// Java program to demonstrate
// withEarlierOffsetAtOverlap() method
  
import java.time.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a ZonedDateTime object
        ZonedDateTime zonedDT
            = ZonedDateTime
                  .ofLocal(
                      LocalDateTime.of(2021, 11, 07, 1, 05, 53),
                      ZoneId.of("US/Central"),
                      ZoneOffset.ofHours(-6));
  
        // print ZonedDateTime
        System.out.println("Before"
                           + " withEarlierOffsetAtOverlap():\n "
                           + zonedDT);
  
        // apply withEarlierOffsetAtOverlap()
        ZonedDateTime zonedDT2
            = zonedDT.withEarlierOffsetAtOverlap();
  
        // print ZonedDateTime after
        // withEarlierOffsetAtOverlap()
        System.out.println("\nAfter"
                           + " withEarlierOffsetAtOverlap():\n "
                           + zonedDT2);
    }
}

输出。

Before withEarlierOffsetAtOverlap():
 2021-11-07T01:05:53-06:00[US/Central]

After withEarlierOffsetAtOverlap():
 2021-11-07T01:05:53-05:00[US/Central]

参考资料: https://docs.oracle.com/javase/10/docs/api/java/time/ZonedDateTime.html#withEarlierOffsetAtOverlap()