package com.javarush.task.task08.task0820; import java.util.HashSet; import java.util.Set; /* 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> result = new HashSet<Cat>(); result.add(new Cat()); result.add(new Cat()); result.add(new Cat()); result.add(new Cat()); return result; } public static Set<Dog> createDogs() { Set<Dog> result = new HashSet<>(); result.add(new Dog()); result.add(new Dog()); result.add(new Dog()); return result; } public static Set<Object> join(Set<Cat> cats, Set<Dog> dogs) { Set<Object> pet = new HashSet<>(); pet.addAll(cats); pet.addAll(dogs); return pet; } public static void removeCats(Set<Object> pets, Set<Cat> cats) { pets.removeAll(cats); } public static void printPets(Set<Object> pets) { for(Object c: pets) { System.out.println(c); } } public static class Cat { } public static class Dog { } }