admin.addRole("role4", null, null);
assertEquals(7, admin.getRoleNames().length);//admin,everyone,role1,role2,role3,role4
//Test delete role method
assertTrue(admin.isExistingRole("role3"));
admin.deleteRole("role3");
admin.deleteRole("role4");
assertFalse(admin.isExistingRole("role3"));
admin.addRole("role3", null, null);
admin.addRole("role4", null, null);