@Test
public void createMeShouldUseUniqueCodes() {

    final List<Integer> uniqueCodes = new ArrayList<>();
    for (int i = 0; i < 100; i++) {
        final User me = meFactory.createMe();
        final int code = me.getCode();
        assertFalse(uniqueCodes.contains(code));
        assertTrue(code >= 10000000);
        assertTrue(code <= 20000000);
        uniqueCodes.add(code);
    }
    assertEquals(100, uniqueCodes.size());
}