### Question:
MemoryStore implements Store { public static MemoryStore getInstance() { return INSTANCE; } private  MemoryStore(); static MemoryStore getInstance(); @Override void add(final User newUser); @Override void update(final User newUser); @Override void delete(final int userId); @Override List<User> findAll(); @Override User findById(final int id); @Override User findByLogin(String login);  }### Answer:
@Test public void ifGetTwoInstanceThenTheyShouldBeOneObject() { MemoryStore secondTestStore = MemoryStore.getInstance(); assertThat(this.testStore, is(secondTestStore)); }