groups = acl.getGroups();
assertEquals(0, groups.size());
assertFalse(groups.contains("tardis"));
assertEquals("drwho ", acl.getAclString());
acl.removeUser("drwho");
assertEquals(0, users.size());
assertFalse(users.contains("drwho"));
assertEquals(0, acl.getGroups().size());
assertEquals(0, acl.getUsers().size());
assertEquals(" ", acl.getAclString());