подскажите ,пожалуйста, не могу найти ошибку
package com.javarush.task.task08.task0820;
import java.util.HashSet;
import java.util.Set;
import java.util.Iterator;
/*
Множество всех животных
*/
public class Solution {
public static void main(String[] args) {
Set<Cat> cats = createCats();
Set<Dog> dogs = createDogs();
Set<Object> pets = join(cats, dogs);
printPets(pets);
removeCats(pets, cats);
printPets(pets);
}
public static Set<Cat> createCats() {
Set<Cat> cats = new HashSet<Cat>();
Cat cat1 = new Cat();
Cat cat2 = new Cat();
Cat cat3 = new Cat();
Cat cat4 = new Cat();
cats.add(cat1);
cats.add(cat2);
cats.add(cat3);
cats.add(cat4);
return cats ;
}
public static Set<Dog> createDogs() {
Set<Dog> dogs = new HashSet<Dog>();
Dog dog1 = new Dog();
Dog dog2 = new Dog();
Dog dog3 = new Dog();
return dogs ;
}
public static Set<Object> join(Set<Cat> cats, Set<Dog> dogs) {
Set<Object> result =new HashSet<>();
Iterator Cat =cats.iterator();
while(Cat.hasNext()){
result.add(cats);
}
Iterator Dog = dogs.iterator();
while(Dog.hasNext()){
result.add(dogs);
}
return result ;
}
public static void removeCats(Set<Object> pets, Set<Cat> cats) {
pets.removeAll(cats);
}
public static void printPets(Set<Object> pets) {
Iterator iterator = pets.iterator();
for(Object o : pets){
System.out.println(o);
}
}
public static class Cat{
}
public static class Dog {
}
}