001/*
002 * (C) Copyright 2010 Nuxeo SAS (http://nuxeo.com/) and contributors.
003 *
004 * All rights reserved. This program and the accompanying materials
005 * are made available under the terms of the GNU Lesser General Public License
006 * (LGPL) version 2.1 which accompanies this distribution, and is available at
007 * http://www.gnu.org/licenses/lgpl.html
008 *
009 * This library is distributed in the hope that it will be useful,
010 * but WITHOUT ANY WARRANTY; without even the implied warranty of
011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
012 * Lesser General Public License for more details.
013 * Contributors:
014 * Nuxeo - initial API and implementation
015 */
016
017package org.nuxeo.ecm.platform.rendition.impl;
018
019import java.util.List;
020
021import org.nuxeo.ecm.core.api.Blob;
022import org.nuxeo.ecm.platform.rendition.Rendition;
023import org.nuxeo.ecm.platform.rendition.service.RenditionDefinition;
024
025/**
026 * Implementation of the {@link Rendition} interface that allows lazy computation of the rendition Blobs
027 *
028 * @author <a href="mailto:tdelprat@nuxeo.com">Tiry</a>
029 */
030public abstract class LazyRendition extends AbstractRendition implements Rendition {
031
032    public static final String EMPTY_MARKER = "empty=true";
033
034    protected List<Blob> blobs = null;
035
036    public LazyRendition(RenditionDefinition definition) {
037        super(definition);
038    }
039
040    @Override
041    public Blob getBlob() {
042        List<Blob> blobs = getBlobs();
043        if (blobs != null && blobs.size() > 0) {
044            return blobs.get(0);
045        }
046        return null;
047    }
048
049    @Override
050    public List<Blob> getBlobs() {
051        if (blobs == null) {
052            blobs = computeRenditionBlobs();
053        }
054        return blobs;
055    }
056
057    @Override
058    public boolean isCompleted() {
059        Blob blob = getBlob();
060        if (blob == null) {
061            return true;
062        }
063        String mimeType = blob.getMimeType();
064        // lazy rendition with build in-progress has blob mimeType containing "empty=true"
065        return mimeType == null || !mimeType.contains(EMPTY_MARKER);
066    }
067
068    protected abstract List<Blob> computeRenditionBlobs();
069
070}