handleservlet.java

dspace 用j2ee架构的一个数字图书馆.开源程序

            scope.setTotal(5);

            List items = Browse.getLastSubmitted(scope);

            // Get titles and URLs to item pages
            String[] itemTitles = getItemTitles(items);
            String[] itemLinks = getItemURLs(context, items);

            // is the user a COMMUNITY_EDITOR?
            if (community.canEditBoolean())
            {
                // set a variable to create an edit button
                request.setAttribute("editor_button", new Boolean(true));
            }

            // can they add to this community?
            if (AuthorizeManager.authorizeActionBoolean(context, community,
                    Constants.ADD))
            {
                // set a variable to create an edit button
                request.setAttribute("add_button", new Boolean(true));
            }

            // can they remove from this community?
            if (AuthorizeManager.authorizeActionBoolean(context, community,
                    Constants.REMOVE))
            {
                // set a variable to create an edit button
                request.setAttribute("remove_button", new Boolean(true));
            }

            // Forward to community home page
            request.setAttribute("last.submitted.titles", itemTitles);
            request.setAttribute("last.submitted.urls", itemLinks);
            request.setAttribute("community", community);
            request.setAttribute("collections", collections);
            request.setAttribute("subcommunities", subcommunities);
            JSPManager.showJSP(request, response, "/community-home.jsp");
        }
    }

    /**
     * Show a collection home page, or deal with button press on home page
     * 
     * @param context
     *            Context object
     * @param request
     *            the HTTP request
     * @param response
     *            the HTTP response
     * @param community
     *            the community
     * @param collection
     *            the collection
     */
    private void collectionHome(Context context, HttpServletRequest request,
            HttpServletResponse response, Community community,
            Collection collection) throws ServletException, IOException,
            SQLException, AuthorizeException
    {
        // Handle click on a browse or search button
        if (!handleButton(request, response, collection.getHandle()))
        {
            // Will need to know whether to commit to DB
            boolean updated = false;

            // No search or browse button pressed, check for
            if (request.getParameter("submit_subscribe") != null)
            {
                // Subscribe button pressed.
                // Only registered can subscribe, so redirect unless logged in.
                if (context.getCurrentUser() == null &&
                    !Authenticate
                            .startAuthentication(context, request, response))

                    return;
                else
                {
                    Subscribe.subscribe(context, context.getCurrentUser(),
                            collection);
                    updated = true;
                }
            }
            else if (request.getParameter("submit_unsubscribe") != null)
            {
                Subscribe.unsubscribe(context, context.getCurrentUser(),
                        collection);
                updated = true;
            }

            // display collection home page
            log.info(LogManager.getHeader(context, "view_collection",
                    "collection_id=" + collection.getID()));

            // Find the 5 last submitted items
            BrowseScope scope = new BrowseScope(context);
            scope.setScope(collection);
            scope.setTotal(5);

            List items = Browse.getLastSubmitted(scope);

            // Get titles and URLs to item pages
            String[] itemTitles = getItemTitles(items);
            String[] itemLinks = getItemURLs(context, items);

            // Is the user logged in/subscribed?
            EPerson e = context.getCurrentUser();
            boolean subscribed = false;

            if (e != null)
            {
                subscribed = Subscribe.isSubscribed(context, e, collection);

                // is the user a COLLECTION_EDITOR?
                if (collection.canEditBoolean())
                {
                    // set a variable to create an edit button
                    request.setAttribute("editor_button", new Boolean(true));
                }

                // can they admin this collection?
                if (AuthorizeManager.authorizeActionBoolean(context,
                        collection, Constants.COLLECTION_ADMIN))
                {
                    request.setAttribute("admin_button", new Boolean(true));

                    // give them a button to manage submitter list
                    // what group is the submitter?
                    Group group = collection.getSubmitters();

                    if (group != null)
                    {
                        request.setAttribute("submitters", group);
                    }
                }

                // can they submit to this collection?
                if (AuthorizeManager.authorizeActionBoolean(context,
                        collection, Constants.ADD))
                {
                    request
                            .setAttribute("can_submit_button",
                                    new Boolean(true));

                }
                else
                {
                    request.setAttribute("can_submit_button",
                            new Boolean(false));
                }
            }

            // Forward to collection home page
            request.setAttribute("last.submitted.titles", itemTitles);
            request.setAttribute("last.submitted.urls", itemLinks);
            request.setAttribute("collection", collection);
            request.setAttribute("community", community);
            request.setAttribute("logged.in", new Boolean(e != null));
            request.setAttribute("subscribed", new Boolean(subscribed));
            JSPManager.showJSP(request, response, "/collection-home.jsp");

            if (updated)
            {
                context.complete();
            }
        }
    }

    /**
     * Check to see if a browse or search button has been pressed on a community
     * or collection home page. If so, redirect to the appropriate URL.
     * 
     * @param request
     *            HTTP request
     * @param response
     *            HTTP response
     * @param handle
     *            Handle of the community/collection home page
     * 
     * @return true if a browse/search button was pressed and the user was
     *         redirected
     */
    private boolean handleButton(HttpServletRequest request,
            HttpServletResponse response, String handle) throws IOException
    {
        String button = UIUtil.getSubmitButton(request, "");
        String location = request.getParameter("location");
        String prefix = "/";
        String url = null;

        if (location == null)
        {
            return false;
        }

        /*
         * Work out the "prefix" to which to redirect If "/", scope is all of
         * DSpace, so prefix is "/" If prefix is a handle, scope is a community
         * or collection, so "/handle/1721.x/xxxx/" is the prefix.
         */
        if (!location.equals("/"))
        {
            prefix = "/handle/" + location + "/";
        }

        if (button.equals("submit_titles"))
        {
            // Redirect to browse by title
            url = request.getContextPath() + prefix + "browse-title";
        }
        else if (button.equals("submit_authors"))
        {
            // Redirect to browse authors
            url = request.getContextPath() + prefix + "browse-author";
        }
        else if (button.equals("submit_subjects"))
        {
            // Redirect to browse by date
            url = request.getContextPath() + prefix + "browse-subject";
        }
        else if (button.equals("submit_dates"))
        {
            // Redirect to browse by date
            url = request.getContextPath() + prefix + "browse-date";
        }
        else if (button.equals("submit_search")
                || (request.getParameter("query") != null))
        {
            /*
             * Have to check for search button and query - in some browsers,
             * typing a query into the box and hitting return doesn't produce a
             * submit button parameter. Redirect to appropriate search page
             */
            url = request.getContextPath()
                    + prefix
                    + "simple-search?query="
                    + URLEncoder.encode(request.getParameter("query"),
                            Constants.DEFAULT_ENCODING);
        }

        // If a button was pressed, redirect to appropriate page
        if (url != null)
        {
            response.sendRedirect(response.encodeRedirectURL(url));

            return true;
        }

        return false;
    }

    /**
     * Utility method to obtain the titles for the Items in the given list.
     * 
     * @param List
     *            of Items
     * @return array of corresponding titles
     */
    private String[] getItemTitles(List items)
    {
        String[] titles = new String[items.size()];

        for (int i = 0; i < items.size(); i++)
        {
            Item item = (Item) items.get(i);

            // FIXME: Should probably check for preferred language?
            DCValue[] titlesForThis = item.getDC("title", null, Item.ANY);

            // Just use the first title, if any
            if (titlesForThis.length == 0)
            {
                // No title at all!
                titles[i] = null;
            }
            else
            {
                // Use first title
                titles[i] = titlesForThis[0].value;
            }
        }

        return titles;
    }

    /**
     * Utility method obtain URLs for the most recent items
     * 
     * @param context
     *            DSpace context
     * @param items
     *            the items to get URLs for
     * @return an array of URLs (in Strings) corresponding to those items
     */
    private String[] getItemURLs(Context context, List items)
            throws SQLException
    {
        String[] urls = new String[items.size()];

        for (int i = 0; i < items.size(); i++)
        {
            Item item = (Item) items.get(i);
            urls[i] = "/handle/" + item.getHandle();
        }

        return urls;
    }

    /**
     * Utility method to produce a list of parent communities for a given
     * community, ending with the passed community, if include is true. If
     * commmunity is top-level, the array will be empty, or contain only the
     * passed community, if include is true. The array is ordered highest level
     * to lowest
     */
    private Community[] getParents(Community c, boolean include)
            throws SQLException
    {
        // Find all the "parent" communities for the community
        Community[] parents = c.getAllParents();

        // put into an array in reverse order
        int revLength = include ? (parents.length + 1) : parents.length;
        Community[] reversedParents = new Community[revLength];
        int index = parents.length - 1;

        for (int i = 0; i < parents.length; i++)
        {
            reversedParents[i] = parents[index - i];
        }

        if (include)
        {
            reversedParents[revLength - 1] = c;
        }

        return reversedParents;
    }
}