assertArrayEquals(groups, user.getGroupNames());

        // Test with single group
        groups = new String[] { "users" };
        user = new TestFessUser("testuser", new String[] {}, groups, new String[] {});
        assertArrayEquals(groups, user.getGroupNames());

        // Test with empty groups
        groups = new String[] {};

    }

    @Override
    public String[] getRoleNames() {
        return stream(getRoles()).get(stream -> stream.map(this::decode).toArray(n -> new String[n]));
    }

    @Override
    public String[] getGroupNames() {
        return stream(getGroups()).get(stream -> stream.map(this::decode).toArray(n -> new String[n]));
    }

    private String decode(final String value) {

            return name;
        }

        @Override
        public String[] getRoleNames() {
            return new String[0];
        }

        @Override
        public String[] getGroupNames() {
            return new String[0];
        }

        @Override
        public String[] getPermissions() {
            return permissions;
        }
    }

            return name;
        }

        @Override
        public String[] getRoleNames() {
            return new String[0];
        }

        @Override
        public String[] getGroupNames() {
            return new String[0];
        }

        @Override
        public String[] getPermissions() {
            return permissions;
        }

    }

    @Test

            public void permissionChanged(OptionalThing<FessUserBean> userBean) {
                // Do nothing
            }
        }, "activityHelper");

        String[] groupNames = ldapUser.getGroupNames();
        assertNotNull(groupNames);
        assertEquals(2, groupNames.length);
        assertEquals("group1", groupNames[0]);
        assertEquals("group2", groupNames[1]);
    }

    @Test

                            }
                        });
                        final List<String> newGroupList = stream(user.getGroupNames()).get(stream -> stream.collect(Collectors.toList()));
                        stream(user.getGroupNames()).of(stream -> stream.forEach(name -> {
                            if (oldGroupList.contains(name)) {
                                oldGroupList.remove(name);

        if (logger.isDebugEnabled()) {
            logger.debug("[updateMemberOf] Initial groups/roles set for user: {}. Groups: {}, Roles: {}", user.getName(),
                    Arrays.toString(user.getGroupNames()), Arrays.toString(user.getRoleNames()));
        }

        // Schedule lazy loading of parent groups
        if (!groupIdsForParentLookup.isEmpty()) {
            if (logger.isDebugEnabled()) {