public Period withDays(int numberOfDays)

// Java code to demonstrate withDays() method
  
import java.time.Period;
  
class GFG {
    public static void main(String[] args)
    {
  
        // Get the String to be withDaysd
        String period = "P1Y2M21D";
  
        // Parse the String into Period
        Period p = Period.parse(period);
  
        System.out.println("Period: " + p);
  
        // Get the number of days
        int numberOfDays = 5;
  
        // Change the numberOfDays of this Period
        // using withDays() method
        System.out.println("New Period: "
                           + p.withDays(numberOfDays));
    }
}

Period: P1Y2M21D
New Period: P1Y2M5D

// Java code to demonstrate withDays() method
  
import java.time.Period;
  
class GFG {
    public static void main(String[] args)
    {
  
        // Get the String to be withDaysd
        String period = "-P1Y2M21D";
  
        // Parse the String into Period
        Period p = Period.parse(period);
  
        System.out.println("Period: " + p);
  
        // Get the number of days
        int numberOfDays = -5;
  
        // Change the numberOfDays of this Period
        // using withDays() method
        System.out.println("New Period: "
                           + p.withDays(numberOfDays));
    }
}

Period: P-1Y-2M-21D
New Period: P-1Y-2M-5D