org.silverpeas.core.util.PdfUtil.java Source code

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/*
 * Copyright (C) 2000 - 2018 Silverpeas
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * As a special exception to the terms and conditions of version 3.0 of
 * the GPL, you may redistribute this Program in connection with Free/Libre
 * Open Source Software ("FLOSS") applications as described in Silverpeas's
 * FLOSS exception.  You should have received a copy of the text describing
 * the FLOSS exception, and it is also available here:
 * "https://www.silverpeas.org/legal/floss_exception.html"
 *
 * 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package org.silverpeas.core.util;

import com.lowagie.text.Image;
import com.lowagie.text.Rectangle;
import com.lowagie.text.pdf.PdfContentByte;
import com.lowagie.text.pdf.PdfReader;
import com.lowagie.text.pdf.PdfStamper;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import org.apache.pdfbox.pdmodel.PDDocument;
import org.apache.pdfbox.rendering.PDFRenderer;
import org.silverpeas.core.SilverpeasRuntimeException;
import org.silverpeas.core.util.file.FileUtil;
import org.silverpeas.core.util.logging.SilverLogger;

import javax.imageio.ImageIO;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

/**
 * User: Yohann Chastagnier
 * Date: 08/07/13
 */
public class PdfUtil {

    private static final String PDF_FILE_ERROR_MSG = "The pdf source file doesn't exist";
    private static final String NOT_PDF_FILE_ERROR_MSG = "The source is not a pdf file";
    private static final String PDF_DESTINATION_ERROR_MSG = "The pdf destination file is unknown";

    private PdfUtil() {
        throw new IllegalStateException("Utility class");
    }

    /**
     * Gets some document info from a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @return a {@link DocumentInfo} instance.
     */
    public static DocumentInfo getDocumentInfo(File pdfSource) {
        if (pdfSource == null || !pdfSource.isFile()) {
            throw new SilverpeasRuntimeException(PDF_FILE_ERROR_MSG);
        } else if (!FileUtil.isPdf(pdfSource.getPath())) {
            throw new SilverpeasRuntimeException(NOT_PDF_FILE_ERROR_MSG);
        }
        PdfReader reader = null;
        try (final InputStream pdfSourceIS = FileUtils.openInputStream(pdfSource)) {
            reader = new PdfReader(pdfSourceIS);
            final DocumentInfo documentInfo = new DocumentInfo();
            documentInfo.setNbPages(reader.getNumberOfPages());
            for (int i = 1; i <= documentInfo.getNbPages(); i++) {
                final Rectangle rectangle = reader.getPageSize(i);
                final int maxWidth = Math.round(rectangle.getWidth());
                final int maxHeight = Math.round(rectangle.getHeight());
                if (maxWidth > documentInfo.getMaxWidth()) {
                    documentInfo.setMaxWidth(maxWidth);
                }
                if (maxHeight > documentInfo.getMaxHeight()) {
                    documentInfo.setMaxHeight(maxHeight);
                }
            }
            return documentInfo;
        } catch (Exception e) {
            SilverLogger.getLogger(PdfUtil.class).error(e);
            throw new SilverpeasRuntimeException("A problem has occurred during the reading of a pdf file", e);
        } finally {
            if (reader != null) {
                reader.close();
            }
        }
    }

    /**
     * Converts the first page of a PDF file into a JPEG image.
     * @param pdfSource the source pdf file, this content is not modified by this method.
     * @param imageDestination the destination file of the image representing the first page.
     */
    public static void firstPageAsImage(File pdfSource, File imageDestination) {
        if (pdfSource == null || !pdfSource.isFile()) {
            throw new SilverpeasRuntimeException(PDF_FILE_ERROR_MSG);
        } else if (!FileUtil.isPdf(pdfSource.getPath())) {
            throw new SilverpeasRuntimeException(NOT_PDF_FILE_ERROR_MSG);
        }
        try (final PDDocument document = PDDocument.load(pdfSource)) {
            final PDFRenderer pdfRenderer = new PDFRenderer(document);
            final BufferedImage image = pdfRenderer.renderImage(0);
            ImageIO.write(image, "jpg", imageDestination);
        } catch (Exception e) {
            SilverLogger.getLogger(PdfUtil.class).error(e);
            throw new SilverpeasRuntimeException(
                    "A problem has occurred during the adding of an image into a pdf file", e);
        }
    }

    /**
     * Add a image stamp on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param stampImage the stamp image file
     * @param pdfDestination the destination pdf file, with the stamp in its foreground
     */
    public static void stamp(File pdfSource, File stampImage, File pdfDestination) {
        addImageOnEachPage(pdfSource, stampImage, pdfDestination, false);
    }

    /**
     * Add a image stamp on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param stampImage the stamp image file
     * @param pdfDestination the destination pdf file, with the stamp in its foreground
     */
    public static void stamp(InputStream pdfSource, File stampImage, OutputStream pdfDestination) {
        addImageOnEachPage(pdfSource, stampImage, pdfDestination, false);
    }

    /**
     * Add a image watermark on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param watermarkImage the watermark image file
     * @param pdfDestination the destination pdf file, with the watermark in its background
     */
    public static void watermark(File pdfSource, File watermarkImage, File pdfDestination) {
        addImageOnEachPage(pdfSource, watermarkImage, pdfDestination, true);
    }

    /**
     * Add a image watermark on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param watermarkImage the watermark image file
     * @param pdfDestination the destination pdf file, with the watermark in its background
     */
    public static void watermark(InputStream pdfSource, File watermarkImage, OutputStream pdfDestination) {
        addImageOnEachPage(pdfSource, watermarkImage, pdfDestination, true);
    }

    /**
     * Add a image under or over content on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param image the image file
     * @param pdfDestination the destination pdf file, with the image under or over content
     * @param isBackground indicates if image is addes under or over the content of the pdf source
     * file
     */
    private static void addImageOnEachPage(File pdfSource, File image, File pdfDestination,
            final boolean isBackground) {
        if (pdfSource == null || !pdfSource.isFile()) {
            throw new SilverpeasRuntimeException(PDF_FILE_ERROR_MSG);
        } else if (!FileUtil.isPdf(pdfSource.getPath())) {
            throw new SilverpeasRuntimeException(NOT_PDF_FILE_ERROR_MSG);
        } else if (pdfDestination == null) {
            throw new SilverpeasRuntimeException(PDF_DESTINATION_ERROR_MSG);
        }

        FileInputStream pdfSourceIS = null;
        FileOutputStream pdfDestinationIS = null;
        try {
            pdfSourceIS = FileUtils.openInputStream(pdfSource);
            pdfDestinationIS = FileUtils.openOutputStream(pdfDestination);
            addImageOnEachPage(pdfSourceIS, image, pdfDestinationIS, isBackground);
        } catch (IOException e) {
            throw new SilverpeasRuntimeException(
                    "Pdf source file cannot be opened or pdf destination file cannot be created", e);
        } finally {
            IOUtils.closeQuietly(pdfSourceIS);
            IOUtils.closeQuietly(pdfDestinationIS);
        }
    }

    /**
     * Add a image under or over content on each page of a PDF file.
     * @param pdfSource the source pdf file, this content is not modified by this method
     * @param imageToAdd the image file
     * @param pdfDestination the destination pdf file, with the image under or over content
     * @param isBackground indicates if image is addes under or over the content of the pdf source
     * file
     */
    private static void addImageOnEachPage(InputStream pdfSource, File imageToAdd, OutputStream pdfDestination,
            final boolean isBackground) {

        // Verify given arguments
        if (imageToAdd == null || !imageToAdd.isFile()) {
            throw new SilverpeasRuntimeException("The image file doesn't exist");
        } else if (!FileUtil.isImage(imageToAdd.getPath())) {
            throw new SilverpeasRuntimeException("The picture to add is not an image file");
        }

        PdfReader reader = null;
        try {

            // Get a reader of PDF content
            reader = new PdfReader(pdfSource);

            // Obtain the total number of pages
            int pdfNbPages = reader.getNumberOfPages();
            PdfStamper stamper = new PdfStamper(reader, pdfDestination);

            // Load the image
            Image image = Image.getInstance(imageToAdd.getPath());
            float imageWidth = image.getWidth();
            float imageHeigth = image.getHeight();

            // Adding the image on each page of the PDF
            for (int i = 1; i <= pdfNbPages; i++) {

                // Page sizes
                Rectangle rectangle = reader.getPageSize(i);

                // Compute the scale of the image
                float scale = Math.min(100, (rectangle.getWidth() / imageWidth * 100));
                image.scalePercent(Math.min(scale, (rectangle.getHeight() / imageHeigth * 100)));

                // Setting the image position for the current page
                image.setAbsolutePosition(computeImageCenterPosition(rectangle.getWidth(), image.getScaledWidth()),
                        computeImageCenterPosition(rectangle.getHeight(), image.getScaledHeight()));

                // Adding image
                PdfContentByte imageContainer = isBackground ? stamper.getUnderContent(i)
                        : stamper.getOverContent(i);
                imageContainer.addImage(image);
            }

            // End of the treatment : closing the stamper
            stamper.close();

        } catch (Exception e) {
            SilverLogger.getLogger(PdfUtil.class).error(e);
            throw new SilverpeasRuntimeException(
                    "A problem has occurred during the adding of an image into a pdf file", e);
        } finally {
            if (reader != null) {
                reader.close();
            }
        }
    }

    /**
     * Compute the center position on an axis.
     * @param documentSize the document size.
     * @param imageSize the image size.
     * @return the position of the center of the image to include into document.
     */
    private static float computeImageCenterPosition(float documentSize, float imageSize) {

        // Compute the difference between the two sizes
        float differenceSize = documentSize - imageSize;

        // The center position is the half of the previous result
        return differenceSize / 2;
    }
}