ReferenceHandler.java

/*
 * See the NOTICE file distributed with this work for additional
 * information regarding copyright ownership.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.xwiki.rendering.wikimodel;

/**
 * This utility class splits references to individual parts (hyper-link and
 * label) and delegates to separate methods handling of images, normal
 * references and downloads.
 *
 * @version $Id: 679b712d2f634e9fd86542883e0214add1fba68d $
 * @since 4.0M1
 */
public abstract class ReferenceHandler
{
    public static final String PREFIX_DOWNLOAD = "^(?:d|F)ownload:.*";

    public static final int PREFIX_DOWNLOAD_LEN = "download:".length();

    public static final String PREFIX_IMAGE = "^(?:i|I)mage:.*";

    public static final int PREFIX_IMAGE_LEN = "image:".length();

    private boolean supportImage;

    private boolean supportDownload;

    protected ReferenceHandler(boolean supportImage, boolean supportDownload)
    {
        this.supportImage = supportImage;
        this.supportDownload = supportDownload;
    }

    public void handle(WikiReference ref)
    {
        String link = ref.getLink();
        String label = ref.getLabel();
        WikiParameters params = ref.getParameters();

        if (params.getSize() == 0 && label == null) {
            params = params.addParameter("class", "wikimodel-freestanding");
        }

        if (this.supportImage && link.matches(PREFIX_IMAGE)) {
            link = link.substring(PREFIX_IMAGE_LEN);
            if (label == null || "".equals(label)) {
                label = link;
            }
            handleImage(link, label, params);
        } else if (this.supportDownload && link.matches(PREFIX_DOWNLOAD)) {
            link = link.substring(PREFIX_DOWNLOAD_LEN);
            if (label == null || "".equals(label)) {
                label = link;
            }
            handleDownload(link, label, params);
        } else {
            if (label == null || "".equals(label)) {
                label = link;
            }
            handleReference(link, label, params);
        }
    }

    protected void handleDownload(
        String ref,
        String label,
        WikiParameters params)
    {
        handleReference(ref, label, params);
    }

    protected abstract void handleImage(
        String ref,
        String label,
        WikiParameters params);

    protected abstract void handleReference(
        String ref,
        String label,
        WikiParameters params);
}