handleservlet.java

dspace 用j2ee架构的一个数字图书馆.开源程序

/*
 * HandleServlet.java
 *
 * Version: $Revision: 1.21 $
 *
 * Date: $Date: 2006/01/12 21:47:30 $
 *
 * Copyright (c) 2002-2005, Hewlett-Packard Company and Massachusetts
 * Institute of Technology.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met:
 *
 * - Redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution.
 *
 * - Neither the name of the Hewlett-Packard Company nor the name of the
 * Massachusetts Institute of Technology nor the names of their
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
 * TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE
 * USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGE.
 */
package org.dspace.app.webui.servlet;

import java.io.IOException;
import java.net.URLEncoder;
import java.sql.SQLException;
import java.util.List;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import org.apache.log4j.Logger;
import org.dspace.app.webui.util.Authenticate;
import org.dspace.app.webui.util.JSPManager;
import org.dspace.app.webui.util.UIUtil;
import org.dspace.authorize.AuthorizeException;
import org.dspace.authorize.AuthorizeManager;
import org.dspace.browse.Browse;
import org.dspace.browse.BrowseScope;
import org.dspace.content.Collection;
import org.dspace.content.Community;
import org.dspace.content.DCValue;
import org.dspace.content.DSpaceObject;
import org.dspace.content.Item;
import org.dspace.core.Constants;
import org.dspace.core.Context;
import org.dspace.core.LogManager;
import org.dspace.eperson.EPerson;
import org.dspace.eperson.Group;
import org.dspace.eperson.Subscribe;
import org.dspace.handle.HandleManager;

/**
 * Servlet for handling requests within a community or collection. The Handle is
 * extracted from the URL, e.g: <code>/community/1721.1/1234</code>. If there
 * is anything after the Handle, the request is forwarded to the appropriate
 * servlet. For example:
 * <P>
 * <code>/community/1721.1/1234/simple-search</code>
 * <P>
 * would be forwarded to <code>/simple-search</code>. If there is nothing
 * after the Handle, the community or collection home page is shown.
 * <P>
 * If the initial parameter " **FIXME**
 * 
 * @author Robert Tansley
 * @version $Revision: 1.21 $
 */
public class HandleServlet extends DSpaceServlet
{
    /** log4j category */
    private static Logger log = Logger.getLogger(DSpaceServlet.class);

    /** Is this servlet for dealing with collections? */
    private boolean collections;

    public void init()
    {
        // Sort out what we're dealing with default is titles
        String param = getInitParameter("location");

        collections = ((param != null) && param.equalsIgnoreCase("collections"));
    }

    protected void doDSGet(Context context, HttpServletRequest request,
            HttpServletResponse response) throws ServletException, IOException,
            SQLException, AuthorizeException
    {
        String handle = null;
        String extraPathInfo = null;
        DSpaceObject dso = null;

        // Original path info, of the form "1721.x/1234"
        // or "1721.x/1234/extra/stuff"
        String path = request.getPathInfo();

        if (path != null)
        {
            // substring(1) is to remove initial '/'
            path = path.substring(1);

            try
            {
                // Extract the Handle
                int firstSlash = path.indexOf('/');
                int secondSlash = path.indexOf('/', firstSlash + 1);

                if (secondSlash != -1)
                {
                    // We have extra path info
                    handle = path.substring(0, secondSlash);
                    extraPathInfo = path.substring(secondSlash);
                }
                else
                {
                    // The path is just the Handle
                    handle = path;
                }
            }
            catch (NumberFormatException nfe)
            {
                // Leave handle as null
            }
        }

        // Find out what the handle relates to
        if (handle != null)
        {
            dso = HandleManager.resolveToObject(context, handle);
        }

        if (dso == null)
        {
            log.info(LogManager
                    .getHeader(context, "invalid_id", "path=" + path));
            JSPManager.showInvalidIDError(request, response, path, -1);

            return;
        }

        // OK, we have a valid Handle. What is it?
        if (dso.getType() == Constants.ITEM)
        {
            // Display the item page
            displayItem(context, request, response, (Item) dso, handle);
        }
        else if (dso.getType() == Constants.COLLECTION)
        {
            Collection c = (Collection) dso;

            // Store collection location in request
            request.setAttribute("dspace.collection", c);

            /*
             * Find the "parent" community the collection, mainly for
             * "breadcrumbs" FIXME: At the moment, just grab the first community
             * the collection is in. This should probably be more context
             * sensitive when we have multiple inclusion.
             */
            Community[] parents = c.getCommunities();
            request.setAttribute("dspace.community", parents[0]);

            /*
             * Find all the "parent" communities for the collection for
             * "breadcrumbs"
             */
            request.setAttribute("dspace.communities", getParents(parents[0],
                    true));

            // home page, or forward to another page?
            if (extraPathInfo == null)
            {
                collectionHome(context, request, response, parents[0], c);
            }
            else
            {
                // Forward to another servlet
                request.getRequestDispatcher(extraPathInfo).forward(request,
                        response);
            }
        }
        else if (dso.getType() == Constants.COMMUNITY)
        {
            Community c = (Community) dso;

            // Store collection location in request
            request.setAttribute("dspace.community", c);

            /*
             * Find all the "parent" communities for the community
             */
            request.setAttribute("dspace.communities", getParents(c, false));

            // home page, or forward to another page?
            if (extraPathInfo == null)
            {
                communityHome(context, request, response, c);
            }
            else
            {
                // Forward to another servlet
                request.getRequestDispatcher(extraPathInfo).forward(request,
                        response);
            }
        }
        else
        {
            // Shouldn't happen. Log and treat as invalid ID
            log.info(LogManager.getHeader(context,
                    "Handle not an item, collection or community", "handle="
                            + handle));
            JSPManager.showInvalidIDError(request, response, path, -1);

            return;
        }
    }

    /**
     * Show an item page
     * 
     * @param context
     *            Context object
     * @param request
     *            the HTTP request
     * @param response
     *            the HTTP response
     * @param item
     *            the item
     * @param handle
     *            the item's handle
     */
    private void displayItem(Context context, HttpServletRequest request,
            HttpServletResponse response, Item item, String handle)
            throws ServletException, IOException, SQLException,
            AuthorizeException
    {
        // Tombstone?
        if (item.isWithdrawn())
        {
            JSPManager.showJSP(request, response, "/tombstone.jsp");

            return;
        }

        // Ensure the user has authorisation
        AuthorizeManager.authorizeAction(context, item, Constants.READ);

        log
                .info(LogManager.getHeader(context, "view_item", "handle="
                        + handle));

        // show edit link
        if (item.canEdit())
        {
            // set a variable to create an edit button
            request.setAttribute("admin_button", new Boolean(true));
        }

        // Get the collections
        Collection[] collections = item.getCollections();

        // For the breadcrumbs, get the first collection and the first community
        // that is in. FIXME: Not multiple-inclusion friendly--should be
        // smarter, context-sensitive
        request.setAttribute("dspace.collection", item.getOwningCollection());

        Community[] comms = item.getOwningCollection().getCommunities();
        request.setAttribute("dspace.community", comms[0]);

        /*
         * Find all the "parent" communities for the collection
         */
        request.setAttribute("dspace.communities", getParents(comms[0], true));

        // Full or simple display?
        boolean displayAll = false;
        String modeParam = request.getParameter("mode");

        if ((modeParam != null) && modeParam.equalsIgnoreCase("full"))
        {
            displayAll = true;
        }

        // Set attributes and display
        request.setAttribute("display.all", new Boolean(displayAll));
        request.setAttribute("item", item);
        request.setAttribute("collections", collections);
        JSPManager.showJSP(request, response, "/display-item.jsp");
    }

    /**
     * Show a community 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
     */
    private void communityHome(Context context, HttpServletRequest request,
            HttpServletResponse response, Community community)
            throws ServletException, IOException, SQLException
    {
        // Handle click on a browse or search button
        if (!handleButton(request, response, community.getHandle()))
        {
            // No button pressed, display community home page
            log.info(LogManager.getHeader(context, "view_community",
                    "community_id=" + community.getID()));

            // Get the collections within the community
            Collection[] collections = community.getCollections();

            // get any subcommunities of the community
            Community[] subcommunities = community.getSubcommunities();

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