PDFBox 打印带背景的文件速度慢

打印慢的原因

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java的RasterPrinterJob会执行很多次printPage方法

他应该是按块填充的, 如果页面元素非常复杂, 那么printPage方法可能会执行十几次.

而如果你用了如下代码中流式打印的方式, 每页pdf单独实现Printable接口, 重写print方法.

     private static class FinePrintableDemo implements Printable {

         public FinePrintableDemo(PDDocument document, int index) {
             this.index = index;
             this.printable = new PDFPrintable(document);
         }

         private int index;
         private PDFPrintable printable;

         @Override
         public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
             long start1 = System.currentTimeMillis();
             int res = printable.print(graphics, pageFormat, index);
             long end1 = System.currentTimeMillis();
             System.out.println("打印第 " + (index + 1) + "页 耗时 : " + (end1 - start1) +" 毫秒 ");

             return res;
         }
     }

会发现print方法同样被执行了十几次, 造成一个带背景的pdf打印耗时十几秒.

慢在哪

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慢在每次都重复解析同一页pdf内容. 打了断点后会发现每页都在PDFStreamEngine.processStream

     public void renderPageToGraphics(int pageIndex, Graphics2D graphics, float scale) throws IOException {
         PDPage page = this.document.getPage(pageIndex);
         this.transform(graphics, page, scale);
         PDRectangle cropBox = page.getCropBox();
         graphics.clearRect(0, 0, (int)cropBox.getWidth(), (int)cropBox.getHeight());
         PageDrawerParameters parameters = new PageDrawerParameters(this, page);
         PageDrawer drawer = this.createPageDrawer(parameters);
         drawer.drawPage(graphics, cropBox);
     }

这个方法每次都会消耗1s左右.

怎么解决

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最好的方式自然是改pdfbox源码, 不用每次都重新生成解析pdf文件. 不过那样稍微有点麻烦.

还有个更简单的方式, 既然pdf会被反复解析, 那么我们在print之前把pdf转成图片, 然后直接打印图片即可.

即使RasterPrinterJob.printPage执行十几次, 也不过在绘制Image, 时间会非常短.

因此我们将代码稍微改造下, 在printable.print方法中直接打印图片.

   private static class FinePrintableDemo implements Printable {

         private BufferedImage image;

         public FinePrintableDemo(PDDocument document, int index) {
             // 获取pdf文件, 将其中指定的页面转成图片.
             PDFRenderer renderer = new PDFRenderer(document);
             try {
                 this.image = renderer.renderImage(index, 1, ImageType.RGB);
             } catch (IOException e) {
                 e.printStackTrace();
             }

         }

         @Override
         public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
             long start1 = System.currentTimeMillis();
             Graphics2D g2d = (Graphics2D) graphics.create();
             Paint paint = g2d.getPaint();

             int width = this.image.getWidth();
             int height = this.image.getHeight();

             Shape shape = new Rectangle2D.Double(0, 0, width, height);
             g2d.setPaint(createPaint(shape, StableUtils.isNotSupportARGB(g2d), image, width, height));
             g2d.fill(shape);
             g2d.setPaint(paint);
             g2d.dispose();
             long end1 = System.currentTimeMillis();
             System.out.println("打印第 " + (pageIndex + 1) + "页 耗时 : " + (end1 - start1) +" 毫秒 ");
             return Printable.PAGE_EXISTS;
         }

         private Paint createPaint(Shape shape, boolean isNotSupportARGB, BufferedImage image, int width, int height) {
             Rectangle2D rec2D = shape.getBounds2D();
             if ((int) rec2D.getWidth() <= 0) {
                 rec2D.setRect(rec2D.getX(), rec2D.getY(), rec2D.getWidth() + 40, rec2D.getHeight());
             }
             if ((int) rec2D.getHeight() <= 0) {
                 rec2D.setRect(rec2D.getX(), rec2D.getY(), rec2D.getWidth(), rec2D.getHeight() + 40);
             }
             BufferedImage buffered = new BufferedImage((int) rec2D.getWidth(), (int) rec2D.getHeight(), isNotSupportARGB ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB);
             Graphics2D g2 = buffered.createGraphics();
             GraphHelper.paintImage(g2, (int) rec2D.getWidth(), (int) rec2D.getHeight(), image,
                     Constants.IMAGE_CENTER , Constants.LEFT, Constants.TOP, width, height, isNotSupportARGB);

             g2.dispose();

             return new TexturePaint(buffered, rec2D);
         }
     }

这一次print方法同样被执行了十几次, 但是每次也就十几毫秒, 文件很快就被打印出来了.

完整代码如下

 package com.fr.base;

 import com.fr.stable.Constants;
 import com.fr.stable.StableUtils;
 import org.apache.pdfbox.pdmodel.PDDocument;
 import org.apache.pdfbox.rendering.ImageType;
 import org.apache.pdfbox.rendering.PDFRenderer;

 import java.awt.Graphics;
 import java.awt.Graphics2D;
 import java.awt.Paint;
 import java.awt.Shape;
 import java.awt.TexturePaint;
 import java.awt.geom.Rectangle2D;
 import java.awt.image.BufferedImage;
 import java.awt.print.Book;
 import java.awt.print.PageFormat;
 import java.awt.print.Paper;
 import java.awt.print.Printable;
 import java.awt.print.PrinterException;
 import java.awt.print.PrinterJob;
 import java.io.FileInputStream;
 import java.io.IOException;
 import java.io.InputStream;

 public class doStreamImagePrint {

     public static void main(String[] args) throws IOException, PrinterException {
         PrinterJob job = PrinterJob.getPrinterJob();

         int width = 595;
         int height = 842;
         int marginLeft = 0;
         int marginRight = 0;
         int marginTop = 0;
         int marginBottom = 0;

         Paper paper = new Paper();
         paper.setSize(width, height);
         // 设置边距
         paper.setImageableArea(marginLeft, marginRight, width - (marginLeft + marginRight), height - (marginTop + marginBottom));
         // 自定义页面设置
         PageFormat pageFormat = new PageFormat();
         // 设置页面横纵向
         pageFormat.setOrientation(PageFormat.PORTRAIT);
         pageFormat.setPaper(paper);

         // 构建一个有size的空book, book里都是引用. 实际打印哪一页就从远程获取哪一页
         Book printBook = new Book();
         // 真正打印的时候, 每页的printable都new pdfprintable.print();
         printBook.append(convertPDFToPrint("D:\\bg.pdf", 0), pageFormat);
         printBook.append(convertPDFToPrint("D:\\bg.pdf", 0), pageFormat);

         job.setPageable(printBook);
         job.print();
     }

     private static FinePrintableDemo convertPDFToPrint(String path, int index) throws IOException {
         InputStream in = new FileInputStream(path);
         PDDocument document = PDDocument.load(in);
         return new FinePrintableDemo(document, index);
     }

     private static class FinePrintableDemo implements Printable {

         private BufferedImage image;

         public FinePrintableDemo(PDDocument document, int index) {
             // 获取pdf文件, 将其中指定的页面转成图片.
             PDFRenderer renderer = new PDFRenderer(document);
             try {
                 this.image = renderer.renderImage(index, 1, ImageType.RGB);
             } catch (IOException e) {
                 e.printStackTrace();
             }

         }

         @Override
         public int print(Graphics graphics, PageFormat pageFormat, int pageIndex) throws PrinterException {
             long start1 = System.currentTimeMillis();
             Graphics2D g2d = (Graphics2D) graphics.create();
             Paint paint = g2d.getPaint();

             int width = this.image.getWidth();
             int height = this.image.getHeight();

             Shape shape = new Rectangle2D.Double(0, 0, width, height);
             g2d.setPaint(createPaint(shape, StableUtils.isNotSupportARGB(g2d), image, width, height));
             g2d.fill(shape);
             g2d.setPaint(paint);
             g2d.dispose();
             long end1 = System.currentTimeMillis();
             System.out.println("打印第 " + (pageIndex + 1) + "页 耗时 : " + (end1 - start1) +" 毫秒 ");
             return Printable.PAGE_EXISTS;
         }

         private Paint createPaint(Shape shape, boolean isNotSupportARGB, BufferedImage image, int width, int height) {
             Rectangle2D rec2D = shape.getBounds2D();
             if ((int) rec2D.getWidth() <= 0) {
                 rec2D.setRect(rec2D.getX(), rec2D.getY(), rec2D.getWidth() + 40, rec2D.getHeight());
             }
             if ((int) rec2D.getHeight() <= 0) {
                 rec2D.setRect(rec2D.getX(), rec2D.getY(), rec2D.getWidth(), rec2D.getHeight() + 40);
             }
             BufferedImage buffered = new BufferedImage((int) rec2D.getWidth(), (int) rec2D.getHeight(), isNotSupportARGB ? BufferedImage.TYPE_INT_RGB : BufferedImage.TYPE_INT_ARGB);
             Graphics2D g2 = buffered.createGraphics();
             GraphHelper.paintImage(g2, (int) rec2D.getWidth(), (int) rec2D.getHeight(), image,
                     Constants.IMAGE_CENTER , Constants.LEFT, Constants.TOP, width, height, isNotSupportARGB);

             g2.dispose();

             return new TexturePaint(buffered, rec2D);
         }
     }

 }