Java yearMonth withMonth()方法及示例

YearMonth 类的 withMonth(int month) 方法用来改变YearMonth对象的年月日，使用的是作为参数传递的月份，之后该方法返回改变后的YearMonth的副本。如果指定月份的月日无效，日将被调整为最后的有效月日。这个实例是不可改变的，不受这个方法调用的影响。

语法

public YearMonth withMonth(int month)

参数： 该方法接受 月份 作为参数，即在返回的年月中设置年月，从1（一月）到12（十二月）。

返回值： 该方法返回一个基于该年月的YearMonth，该年月为要求的月份。

异常： 如果年月的值无效，该方法会抛出 DateTimeException 。

下面的程序说明了withMonth()方法：

程序1 :

// Java program to demonstrate
// YearMonth.withMonth() method
  
import java.time.*;
import java.time.temporal.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a YearMonth object
        YearMonth yr
            = YearMonth.of(2019, 12);
  
        // print instance
        System.out.println("YearMonth before"
                           + " applying method: "
                           + yr);
  
        // apply withMonth method of YearMonth class
        YearMonth updatedlocal = yr.withMonth(1);
  
        // print instance
        System.out.println("YearMonth after"
                           + " applying method: "
                           + updatedlocal);
    }
}

输出。

YearMonth before applying method: 2019-12
YearMonth after applying method: 2019-01

程序2

// Java program to demonstrate
// YearMonth.withMonth() method
  
import java.time.*;
import java.time.temporal.*;
  
public class GFG {
    public static void main(String[] args)
    {
  
        // create a YearMonth object
        YearMonth yr
            = YearMonth.of(2022, 7);
  
        // print instance
        System.out.println("YearMonth before"
                           + " applying method: "
                           + yr);
  
        // apply withMonth method of YearMonth class
        YearMonth updatedlocal = yr.withMonth(12);
  
        // print instance
        System.out.println("YearMonth after"
                           + " applying method: "
                           + updatedlocal);
    }
}

输出。

YearMonth before applying method: 2022-07
YearMonth after applying method: 2022-12

参考文献: https: //docs.oracle.com/javase/10/docs/api/java/time/YearMonth.html#withMonth(int)