@Test(expected = WrongReferenceAttributeValueException.class)
public void testCheckWithDuplicate() throws Exception {

	System.out.println("testCheckWithDuplicate()");
	minUid.setValue(2);
	maxUid.setValue(6);
	attributeToCheck.setValue(5);
	List<User> list = new ArrayList<>();
	list.add(user);
	list.add(new User());
	when(session.getPerunBl().getUsersManagerBl().getUsersByAttribute(session, attributeToCheck)).thenReturn(list);
	classInstance.checkAttributeSemantics(session, user, attributeToCheck);
}