How can add interface java file to these three java files that runs together? Java file 1: package property2;

How can add interface java file to these three java files that runs together?

Java file 1:

package property2;

import java.util.Scanner;

public class Property2 {

    
    public static void main(String[] args) {
        
        Scanner in = new Scanner(System.in);
        // Read property name and rent as input values from the keyboard
        System.out.println("Enter property name: ");
        String propertyName=in.nextLine();
        System.out.println("Enter property rent amount: ");
        int rent=Integer.parseInt(in.nextLine());

        Property property = new Apartment(propertyName, rent);
        System.out.println("Property Name: "+property.getPropertyName());
        System.out.println("Property Rent$: "+property.getRentAmount());
    }
}

Java file 2:

package property2;

import javax.lang.model.SourceVersion;

    abstract class Property
{
 protected String propertyName;
 protected int rentAmount;
 public Property(String propertyName, int rentAmount)
 {
  this.propertyName = propertyName;
  this.rentAmount = rentAmount;
 }
 public abstract String getPropertyName();
 public abstract int getRentAmount();

    
    }

Java file 3:

package property2;

class Apartment extends Property 
{
       /*Apartment class constructor that takes two input
     * arguments and calls the constructor of the abstract class*/
    public Apartment(String PropertyName, int RentAmount) 
    {
        super(PropertyName, RentAmount);
    }
    @Override
    /*
     * Return propertyName value
     * */
    public String getPropertyName() {
        return propertyName;     
    }
    @Override
    /*
     * Return rentAmount value
     * */
    public int getRentAmount() {
      return rentAmount;
    }
}