Объясните кто нибудь или киньте материал лекции где описывается данное явление, не понимаю почему ниже обязательно нужно писать parent.name а не просто parent, также и с secondparent, и важен ли порядок считывания текста и создания объектов?
package com.javarush.task.task06.task0621;
import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
/*
Родственные связи кошек
*/
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
String grandpaName = reader.readLine();
Cat catgrandpa = new Cat(grandpaName);
String grandmaName = reader.readLine();
Cat catgrandma = new Cat(grandmaName);
String fatherName = reader.readLine();
Cat catfather = new Cat(fatherName, catgrandpa);
String motherName = reader.readLine();
Cat catMother = new Cat(motherName,catgrandma);
String sonName = reader.readLine();
Cat catson = new Cat(sonName, catMother, catfather);
String daughterName = reader.readLine();
Cat catDaughter = new Cat(daughterName, catMother, catfather);
System.out.println(catgrandpa);
System.out.println(catgrandma);
System.out.println(catfather);
System.out.println(catMother);
System.out.println(catson);
System.out.println(catDaughter);
}
public static class Cat {
private String name;
private Cat parent;
private Cat secondparent;
Cat(String name) {
this.name = name;
}
Cat(String name, Cat parent) {
this.name = name;
this.parent = parent;
}
Cat(String name,Cat parent, Cat secondparent){
this.name = name;
this.parent = parent;
this.secondparent = secondparent;
}
@Override
public String toString() {
if(parent ==null && secondparent!=null)
return "The cat's name is " + name + ", no mother," + " father is " + secondparent.name;
if(parent !=null && secondparent == null)
return "The cat's name is " + name + ", mother is " + parent.name + ", no father" ;
if(parent !=null && secondparent!=null)
return "The cat's name is " + name + ", mother is " + parent.name + ", father is " + secondparent.name;
else
return "The cat's name is " + name + ", no mother , no father";
}
}
}