digilib.pdf.PDFStreamWorker.java Source code

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Here is the source code for digilib.pdf.PDFStreamWorker.java

Source

package digilib.pdf;

/*
 * #%L
 * PDF worker that creates a PDF document in an OutputStream.
 * %%
 * Copyright (C) 2009 - 2013 MPIWG Berlin
 * %%
 * This program 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.
 * 
 * This program 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 General Lesser Public License for more details.
 * 
 * You should have received a copy of the GNU General Lesser Public 
 * License along with this program.  If not, see
 * <http://www.gnu.org/licenses/lgpl-3.0.html>.
 * #L%
 * Authors: Christopher Mielack,
 *          Robert Casties (robcast@berlios.de)
 */

import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Future;

import org.apache.log4j.Logger;

import com.itextpdf.text.Document;
import com.itextpdf.text.DocumentException;
import com.itextpdf.text.Image;
import com.itextpdf.text.PageSize;
import com.itextpdf.text.pdf.PdfWriter;

import digilib.image.DocuImage;
import digilib.image.ImageJobDescription;
import digilib.image.ImageWorker;
import digilib.conf.DigilibConfiguration;
import digilib.conf.PDFRequest;
import digilib.util.DigilibJobCenter;
import digilib.util.NumRange;

public class PDFStreamWorker implements Callable<OutputStream> {

    protected static Logger logger = Logger.getLogger(PDFStreamWorker.class);

    protected DigilibConfiguration dlConfig = null;

    protected Document doc = null;

    protected OutputStream outstream = null;

    protected PDFRequest job_info = null;

    protected DigilibJobCenter<DocuImage> imageJobCenter = null;

    /**
     * @param dlConfig
     * @param outputfile
     * @param job_info
     */
    public PDFStreamWorker(DigilibConfiguration dlConfig, OutputStream outputfile, PDFRequest job_info,
            DigilibJobCenter<DocuImage> imageJobCenter) {
        super();
        this.dlConfig = dlConfig;
        this.outstream = outputfile;
        this.job_info = job_info;
        this.imageJobCenter = imageJobCenter;
    }

    public OutputStream call() throws Exception {
        outstream = renderPDF();
        return outstream;
    }

    /**
     * @throws DocumentException
     * @throws InterruptedException
     * @throws ExecutionException
     * @throws IOException
     */
    protected OutputStream renderPDF()
            throws DocumentException, InterruptedException, ExecutionException, IOException {
        // create document object
        doc = new Document(PageSize.A4, 0, 0, 0, 0);
        PdfWriter docwriter = null;

        long start_time = System.currentTimeMillis();

        docwriter = PdfWriter.getInstance(doc, outstream);

        setPDFProperties(doc);

        doc.open();

        addTitlePage(doc);

        logger.debug("PDF: " + outstream + " doc.open()ed (" + (System.currentTimeMillis() - start_time) + "ms)");

        NumRange pgs = job_info.getPages();

        for (int p : pgs) {
            logger.debug("PDF: adding Image " + p + " to " + outstream);
            // create ImageJobInformation
            ImageJobDescription iji = ImageJobDescription.getInstance(job_info, job_info.getDlConfig());
            iji.setValue("pn", p);
            addImage(doc, iji);
            logger.debug("PDF: done adding Image " + p + " to " + outstream);
        }

        logger.debug("PDF: done adding all Images to " + outstream);

        doc.close();
        logger.debug("PDF: " + outstream + " doc.close() (" + (System.currentTimeMillis() - start_time) + "ms)");
        docwriter.flush();
        docwriter.close();
        return outstream;
    }

    /**
     * Set PDF-Meta-Attributes.
     */
    public Document setPDFProperties(Document doc) {
        // TODO get proper Information from dlConfig
        doc.addAuthor(this.getClass().getName());
        doc.addCreationDate();
        doc.addKeywords("digilib");
        doc.addTitle("digilib PDF");
        doc.addCreator(this.getClass().getName());
        return doc;
    }

    /**
     * Create a title page and append it to the document (should, of course, be
     * called first)
     * 
     * @throws DocumentException
     */
    public Document addTitlePage(Document doc) throws DocumentException {
        PDFTitlePage titlepage = new PDFTitlePage(job_info);
        doc.add(titlepage.getPageContents());
        doc.newPage();
        return doc;
    }

    /**
     * adds an image to the document.
     * 
     * @param doc
     * @param iji
     * @return
     * @throws InterruptedException
     * @throws ExecutionException
     * @throws IOException
     * @throws DocumentException
     */
    public Document addImage(Document doc, ImageJobDescription iji)
            throws InterruptedException, ExecutionException, IOException, DocumentException {
        // create image worker
        ImageWorker job = new ImageWorker(dlConfig, iji);
        // submit
        Future<DocuImage> jobTicket = imageJobCenter.submit(job);
        // wait for result
        DocuImage img = jobTicket.get();
        // scale the image
        Image pdfimg = Image.getInstance(img.getAwtImage(), null);
        float docW = PageSize.A4.getWidth() - 2 * PageSize.A4.getBorder();
        float docH = PageSize.A4.getHeight() - 2 * PageSize.A4.getBorder();
        // TODO: do we really scale this again?
        pdfimg.scaleToFit(docW, docH);
        // add to PDF
        doc.add(pdfimg);
        return doc;
    }

}