Методы, решение задачи

public class Airplanes {
    public static void main(String[] args) {
 
        String typePlane1 = "Jet";
        String typePlane2 = "Airliner";
        String modelPlane1 = "F-22";
        String modelPlane2 = "Airbus A-737";
        String modelPlane3 = "Boeing B-777";
 
        int sumEcoClass1 = 100;
        int sumEcoClass2 = 150;
        int sumBusinessClass1 = 30;
 
        String buildAirplane1 = buildAirplane(typePlane1, modelPlane1 );
        String buildAirplane2 = buildAirplane(typePlane2, modelPlane2, sumEcoClass1);
        String buildAirplane3 = buildAirplane(typePlane2, modelPlane3, sumEcoClass2, sumBusinessClass1);
 
        System.out.println("Plane type: " + buildAirplane1);
        System.out.println("Plane type: " + buildAirplane2 + ", number of economy class passengers : " +sumEcoClass1);
        System.out.println("Plane type: " + buildAirplane3 + ", number of economy class passengers : " +sumEcoClass2 + ", number of business class passengers : " + sumBusinessClass1);
 
 
    }
 
    public static String buildAirplane(String a, String b) {
 
        return a + ", model : " + b;
 
    }
    public static String buildAirplane(String  a, String b, int c) {
 
        return a + ", model : " + b + c;
 
    }
    public static String buildAirplane(String a, String b, int c, int d) {
 
        return a + ", model : " + b + c + d;
 
    }
 
}

public class Main {
 
        public static void main(String[] args) {
            Plane plane1 = new Plane();
            Plane plane2 = new Plane();
            Plane plane3 = new Plane();
 
            plane1.buildAirplane("F-1","Jet");
            plane2.buildAirplane("Airbus A-737","Airliner",135);
            plane3.buildAirplane("Boeing B-777","Airliner",214,28);
 
        }
    }
    class Plane
    {
        void buildAirplane(String name, String type){
            System.out.printf("Plane %s have type: %s \n",name,type);
        }
        void buildAirplane(String name, String type, int e){
            System.out.printf("Plane %s have type: %s \nNumber of economy class passengers: %s\n",name,type,e);
        }
        void buildAirplane(String name, String type, int e,int b){
            System.out.printf("Plane %s have type: %s \nNumber of economy class passengers: %s \nNumber of business class passengers :%s\n",name,type,e,b);
        }
    }

class Plane
    {
        void buildAirplane(String name, String type){
            System.out.printf("Plane %s have type: %s \n",name,type);
        }
        void buildAirplane(String name, String type, int e){
            buildAirplane(name,type);
            System.out.printf("Number of economy class passengers: %s\n",e);
        }
        void buildAirplane(String name, String type, int e,int b){
            buildAirplane(name,type,e);
            System.out.printf("Number of business class passengers :%s\n",b);
        }
    }

public class Helper {
 
    public static void main(String[] args) {
        Plane[] planes = new Plane[2];
        planes[0] = PlaneFactory.buildAirplane("F16");
        planes[1] = PlaneFactory.buildAirplane("Ял42", 42);
        System.out.println(Arrays.toString(planes));
    }
}
class PlaneFactory {
    public static MilitPlane buildAirplane(String name){
        return new MilitPlane(name);
    }
 
    public static CivilianPlane buildAirplane(String name, int countPassengers){
        return new CivilianPlane(name, countPassengers);
    }
}
 
class Plane {
    enum TypePlane {MILITARY, CIVILIAN, CARGO}
}
 
class MilitPlane extends Plane {
    TypePlane typePlane = TypePlane.MILITARY;
    private String name;
 
    public MilitPlane(String name) {
        this.name = name;
    }
 
    @Override
    public String toString() {
        return "MilitPlane{" +
                "typePlane=" + typePlane +
                ", name='" + name + '\'' +
                '}';
    }
}
 
class CivilianPlane extends Plane {
    TypePlane typePlane = TypePlane.CIVILIAN;
    private String name;
    private int countPassengers;
 
    public CivilianPlane(String name, int countPassengers) {
        this.name = name;
        this.countPassengers = countPassengers;
    }
 
    @Override
    public String toString() {
        return "CivilianPlane{" +
                "typePlane=" + typePlane +
                ", name='" + name + '\'' +
                ", countPassengers=" + countPassengers +
                '}';
    }
}