org.alfresco.repo.content.transform.AppleIWorksContentTransformer.java Source code

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Here is the source code for org.alfresco.repo.content.transform.AppleIWorksContentTransformer.java

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/*
 * #%L
 * Alfresco Repository
 * %%
 * Copyright (C) 2005 - 2016 Alfresco Software Limited
 * %%
 * This file is part of the Alfresco software. 
 * If the software was purchased under a paid Alfresco license, the terms of 
 * the paid license agreement will prevail.  Otherwise, the software is 
 * provided under the following open source license terms:
 * 
 * Alfresco 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 3 of the License, or
 * (at your option) any later version.
 * 
 * Alfresco 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.
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package org.alfresco.repo.content.transform;

import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;

import org.alfresco.error.AlfrescoRuntimeException;
import org.alfresco.repo.content.MimetypeMap;
import org.alfresco.service.cmr.repository.ContentReader;
import org.alfresco.service.cmr.repository.ContentWriter;
import org.alfresco.service.cmr.repository.TransformationOptions;
import org.apache.commons.compress.archivers.zip.ZipArchiveEntry;
import org.apache.commons.compress.archivers.zip.ZipArchiveInputStream;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Converts Apple iWorks files to PDFs or JPEGs for thumbnailing & previewing.
 * The transformer will only work for iWorks 09 files and later as previous versions of those files
 * were actually saved as directories.
 * 
 * @author Neil Mc Erlean
 * @since 4.0
 */
public class AppleIWorksContentTransformer extends AbstractContentTransformer2 {
    private static final Log log = LogFactory.getLog(AppleIWorksContentTransformer.class);

    // Apple's zip entry names for the front-page and all-doc previews in iWorks.
    // We don't attempt to parse the XML 'manifest' (index.xml) within the iWorks file.
    private static final String QUICK_LOOK_PREVIEW_PDF = "QuickLook/Preview.pdf";
    private static final String QUICK_LOOK_THUMBNAIL_JPG = "QuickLook/Thumbnail.jpg";

    private static final List<String> IWORKS_MIMETYPES = Arrays
            .asList(new String[] { MimetypeMap.MIMETYPE_IWORK_KEYNOTE, MimetypeMap.MIMETYPE_IWORK_NUMBERS,
                    MimetypeMap.MIMETYPE_IWORK_PAGES });
    private static final List<String> TARGET_MIMETYPES = Arrays
            .asList(new String[] { MimetypeMap.MIMETYPE_IMAGE_JPEG, MimetypeMap.MIMETYPE_PDF });

    @Override
    public boolean isTransformable(String sourceMimetype, String targetMimetype, TransformationOptions options) {
        // only support [iWorks] -> JPEG | PDF
        // This is because iWorks 09+ files are zip files containing embedded jpeg/pdf previews.
        return TARGET_MIMETYPES.contains(targetMimetype) && IWORKS_MIMETYPES.contains(sourceMimetype);
    }

    @Override
    public String getComments(boolean available) {
        return getCommentsOnlySupports(IWORKS_MIMETYPES, TARGET_MIMETYPES, available);
    }

    @Override
    protected void transformInternal(ContentReader reader, ContentWriter writer, TransformationOptions options)
            throws Exception {
        final String sourceMimetype = reader.getMimetype();
        final String sourceExtension = getMimetypeService().getExtension(sourceMimetype);
        final String targetMimetype = writer.getMimetype();

        if (log.isDebugEnabled()) {
            StringBuilder msg = new StringBuilder();
            msg.append("Transforming from ").append(sourceMimetype).append(" to ").append(targetMimetype);
            log.debug(msg.toString());
        }

        ZipArchiveInputStream iWorksZip = null;
        try {
            // iWorks files are zip files (at least in recent versions, iWork 09).
            // If it's not a zip file, the resultant ZipException will be caught as an IOException below.
            iWorksZip = new ZipArchiveInputStream(reader.getContentInputStream());

            ZipArchiveEntry entry = null;
            boolean found = false;
            while (!found && (entry = iWorksZip.getNextZipEntry()) != null) {
                if (MimetypeMap.MIMETYPE_IMAGE_JPEG.equals(targetMimetype)
                        && entry.getName().equals(QUICK_LOOK_THUMBNAIL_JPG)) {
                    writer.putContent(iWorksZip);
                    found = true;
                } else if (MimetypeMap.MIMETYPE_PDF.equals(targetMimetype)
                        && entry.getName().equals(QUICK_LOOK_PREVIEW_PDF)) {
                    writer.putContent(iWorksZip);
                    found = true;
                }
            }

            if (!found) {
                throw new AlfrescoRuntimeException(
                        "Unable to transform " + sourceExtension + " file to " + targetMimetype);
            }
        } catch (FileNotFoundException e1) {
            throw new AlfrescoRuntimeException("Unable to transform " + sourceExtension + " file.", e1);
        } catch (IOException e) {
            throw new AlfrescoRuntimeException("Unable to transform " + sourceExtension + " file.", e);
        } finally {
            if (iWorksZip != null) {
                iWorksZip.close();
            }
        }
    }
}