public IteratorProxy(int type, Iterator iterator, Authorization authorization,
            ForumPermissions permissions)
    {
        this.iterator = iterator;
        this.authorization = authorization;
        this.permissions = permissions;
 
        // Load the appropriate proxy factory depending on the type of object
        // that we're iterating through. Each proxy factory is responsible
        // for checking that the user has permission to view the object, and
        // then wrapping it with an appropriate proxy.
        switch (type) {
            // CATEGORY
            case JiveGlobals.FORUM_CATEGORY:
                // Create a class that wraps forums with proxies.
                proxyFactory = new ProxyFactory() {
                    public Object createProxy(Object obj, Authorization auth,
                            ForumPermissions perms)
                    {
                        ForumCategory category = (ForumCategory)obj;
                        // Create a new permissions object with the combination
                        // of the permissions of this object and tempPermissions.
                        int parentPerms = perms.toInt();
                        // Never inherit the show category permission.
                        ForumPermissions newPerms = new ForumPermissions(
                                ForumPermissions.setBit(parentPerms,
                                ForumPermissions.SHOW_CATEGORY, false));
                        ForumPermissions catPerms = category.getPermissions(auth);
                        newPerms = new ForumPermissions(catPerms, newPerms);
 
                        // Return the object if the user has permission.
                        if (newPerms.get(ForumPermissions.READ_FORUM) ||
                            newPerms.get(ForumPermissions.SHOW_CATEGORY) ||
                            newPerms.get(ForumPermissions.MODERATE_MESSAGES) ||
                            newPerms.get(ForumPermissions.MODERATE_THREADS) ||
                            newPerms.get(ForumPermissions.FORUM_ADMIN) ||
                            newPerms.get(ForumPermissions.CATEGORY_ADMIN) ||
                            newPerms.get(ForumPermissions.SYSTEM_ADMIN))
                        {
                            return new ForumCategoryProxy(category, auth, newPerms);
                        }
                        // Otherwise return null.
                        else {
                            return null;
                        }
                    }
                };
                break;

public Object getNextElement() {
        while (iterator.hasNext()) {
            Object element = proxyFactory.createProxy(iterator.next(),
                    authorization, permissions);
            if (element != null) {
                return element;
            }
        }
        return null;
    }