Java中的 OffsetDateTime withNano() 方法及示例

Java中 OffsetDateTime 类的withNano()方法返回此 OffsetDateTime 的副本，其中纳秒更改为参数中指定的。

句法：

public OffsetDateTime withNano(int nanoOfSecond)

参数：此方法接受单个参数nanaOfSecond ，它指定要在结果中设置的纳秒，范围可以从 0 到 999、999、999..

返回值：它返回一个基于此日期的 OffsetDateTime 请求的纳秒且不为空。

异常：当纳秒值无效时，程序会抛出DateTimeException 。

下面的程序说明了withNano()方法：

方案一：

// Java program to demonstrate the withNano() method
  
import java.time.OffsetDateTime;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // Parses the date1
        OffsetDateTime date1
            = OffsetDateTime
                  .parse(
                      "2018-12-12T13:30:30+05:00");
  
        // Prints dates
        System.out.println("Date1: " + date1);
  
        // Changes the nano-of-second
        System.out.println("Date1 after altering nano-of-second: "
                           + date1.withNano(1000));
    }
}

输出：

Date1: 2018-12-12T13:30:30+05:00
Date1 after altering nano-of-second: 2018-12-12T13:30:30.000001+05:00

方案二：

// Java program to demonstrate the withNano() method
  
import java.time.OffsetDateTime;
  
public class GFG {
    public static void main(String[] args)
    {
  
        try {
  
            // Parses the date1
            OffsetDateTime date1
                = OffsetDateTime
                      .parse(
                          "2018-12-12T13:30:30+05:00");
  
            // Prints dates
            System.out.println("Date1: " + date1);
  
            // Changes the nano-of-second
            System.out.println("Date1 after altering nano-of-second: "
                               + date1.withNano(1000000000));
        }
        catch (Exception e) {
            System.out.println("Exception: " + e);
        }
    }
}

输出：

Date1: 2018-12-12T13:30:30+05:00
Exception: java.time.DateTimeException: 
           Invalid value for NanoOfSecond (valid values 0 - 999999999): 1000000000

参考：https: Java/time/OffsetDateTime.html#withNano(int)