class Person {
    private String firstName;
    private String secondName;
    private String lastName;
    private int age;
    private String address;

    private Person(String firstName, String lastName) {
        this.firstName = firstName;
        this.lastName = lastName;
    }

    public static Person of(String firstName, String lastName) {
        return new Person(firstName, lastName);
    }

    public Person secondName(String secondName) {
        this.secondName = secondName;
        return this;
    }

    public Person age(int age) {
        this.age = age;
        return this;
    }

    public Person address(String address) {
        this.address = address;
        return this;
    }

    @Override
    public String toString() {
        return "Person{" +
                "firstName='" + firstName + '\'' +
                ", secondName='" + secondName + '\'' +
                ", lastName='" + lastName + '\'' +
                ", age=" + age +
                ", address='" + address + '\'' +
                '}';
    }
}

public class Main {
    public static void main(String[] args) {
        Person john = Person.of("John", "Smith").secondName("William").age(30);

        System.out.println(john);
    }
}