public SimpleAuthenticationConfig addUser(@Nonnull String username, @Nonnull String password, String... roles) {
        addUser(username, new UserDto(password, roles));
        return self();
    }
@Test
    public void testAddUser() {
        SimpleAuthenticationConfig c = new SimpleAuthenticationConfig();
        c.addUser("user1", "password1");
        c.addUser("user2", "password2", "role1");
        c.addUser("user3", "password3", "role1", "role2", "role3");
        assertEquals(3, c.getUsernames().size());
        assertEquals("password1", c.getPassword("user1"));
        assertTrue(c.getRoles("user3").contains("role3"));
    }