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使用PDFBox处理PDF文档

2019-11-10 18:43:37
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使用PDFBox处理PDF文档(新建PDF文件、修改PDF文件、PDF中插入图片、将PDF文件转换为图片)

阅读:4462 时间:2015-01-26 20:07分享:7

项目需要在原有的PDF文件中插入图片、文字,并将最终的PDF文件转换为图片,在网上找了很多Demo,现在开源可以解析处理PDF文件的第三方插件比较多,eg:IText、PDFBox等,现在就PDFBox解析处理PDF文件总结如下:

 

【PDFBox简介】

自从Adobe公司1993年第一次发布公共PDF参考以来,支持各种语言和平台的PDF工具和类库就如雨后春笋般涌现。然而,java应用开发中Adobe技术的支持相对滞后了。这是个奇怪的现象,因为PDF文档是企业信息系统存储和交换信息的大势所趋,而Java技术特别适合这种应用。然而,Java开发人员似乎直到最近才获得成熟可用的PDF支持。   PDFBox(一个BSD许可下的源码开放项目)是一个为开发人员读取和创建PDF文档而准备的纯Java类库。它提供如下特性: 提取文本,包括Unicode字符。和Jakarta Lucene等文本搜索引擎的整合过程十分简单。加密/解密PDF文档。从PDF和XFDF格式中导入或导出表单数据。向已有PDF文档中追加内容。将一个PDF文档切分为多个文档。覆盖PDF文档。   PS:http://baike.baidu.com/link?url=TsYWHJtTPMhlf0UvKzPOk-j3f9KzF7morIa4CqoZ0s4yIDCLB3z8nLVgLHVz-AO4dE6S7ls_3_yuvXP03nLSiq  

【PDFBox下载】

最常见的一种PDF文本抽取工具就是PDFBox了,访问网址http://pdfbox.apache.org/download.cgi,进入如下图所示的下载界面。读者可以在该网页下载其最新的版本。本书采用的是pdfbox-1.8.8版本。PDFBox是一个开源的Java PDF库,这个库允许你访问PDF文件的各项信息。在接下来的例子中,将演示如何使用PDFBox提供的API操作PDF文件。

 

【将刚下载的7个jar包引入到工程当中】

pdfbox-1.8.8-src.zip为pdfbox源代码,里面有很对的例子,在pdfbox-1.8.8/examples目录下存在

 

【以下为Demo正式开始】

1、创建PDF文件

 

 1     public void createHelloPDF() { 2         PDDocument doc = null; 3         PDPage page = null; 4  5         try { 6             doc = new PDDocument(); 7             page = new PDPage(); 8             doc.addPage(page); 9             PDFont font = PDType1Font.HELVETICA_BOLD;10             PDPageContentStream content = new PDPageContentStream(doc, page);11             content.beginText();12             content.setFont(font, 12);13             content.moveTextPositionByAmount(100, 700);14             content.drawString("hello");15 16             content.endText();17             content.close();18             doc.save("F://java56班//eclipse-SDK-4.2-win32//pdfwithText.pdf");19             doc.close();20         } catch (Exception e) {21             System.out.PRintln(e);22         }23     }

 

2、读取PDF文件:

 1     public void readPDF() { 2         PDDocument helloDocument = null; 3         try { 4             helloDocument = PDDocument.load(new File( 5                     "F://java56班//eclipse-SDK-4.2-win32//pdfwithText.pdf")); 6             PDFTextStripper textStripper = new PDFTextStripper("GBK"); 7             System.out.println(textStripper.getText(helloDocument)); 8  9             helloDocument.close();10         } catch (IOException e) {11             // TODO Auto-generated catch block12             e.printStackTrace();13         }14     }

3、修改PDF文件(处理中文乱码,我可以搞定的):

 1  /** 2      * Locate a string in a PDF and replace it with a new string. 3      * 4      * @param inputFile The PDF to open. 5      * @param outputFile The PDF to write to. 6      * @param strToFind The string to find in the PDF document. 7      * @param message The message to write in the file. 8      * 9      * @throws IOException If there is an error writing the data.10      * @throws COSVisitorException If there is an error writing the PDF.11      */12     public void doIt( String inputFile, String outputFile, String strToFind, String message)13         throws IOException, COSVisitorException14     {15         // the document16         PDDocument doc = null;17         try18         {19             doc = PDDocument.load( inputFile );20 //            PDFTextStripper stripper=new PDFTextStripper("ISO-8859-1");21             List pages = doc.getDocumentCatalog().getAllPages();22             for( int i=0; i<pages.size(); i++ )23             {24                 PDPage page = (PDPage)pages.get( i );25                 PDStream contents = page.getContents();26                 PDFStreamParser parser = new PDFStreamParser(contents.getStream() );27                 parser.parse();28                 List tokens = parser.getTokens();29                 for( int j=0; j<tokens.size(); j++ )30                 {31                     Object next = tokens.get( j );32                     if( next instanceof PDFOperator )33                     {34                         PDFOperator op = (PDFOperator)next;35                         //Tj and TJ are the two operators that display36                         //strings in a PDF37                         if( op.getOperation().equals( "Tj" ) )38                         {39                             //Tj takes one operator and that is the string40                             //to display so lets update that operator41                             COSString previous = (COSString)tokens.get( j-1 );42                             String string = previous.getString();43                             string = string.replaceFirst( strToFind, message );44                             System.out.println(string);45                             System.out.println(string.getBytes("GBK"));46                             previous.reset();47                             previous.append( string.getBytes("GBK") );48                         }49                         else if( op.getOperation().equals( "TJ" ) )50                         {51                             COSArray previous = (COSArray)tokens.get( j-1 );52                             for( int k=0; k<previous.size(); k++ )53                             {54                                 Object arrElement = previous.getObject( k );55                                 if( arrElement instanceof COSString )56                                 {57                                     COSString cosString = (COSString)arrElement;58                                     String string = cosString.getString();59                                     string = string.replaceFirst( strToFind, message );60                                     cosString.reset();61                                     cosString.append( string.getBytes("GBK") );62                                 }63                             }64                         }65                     }66                 }67                 //now that the tokens are updated we will replace the68                 //page content stream.69                 PDStream updatedStream = new PDStream(doc);70                 OutputStream out = updatedStream.createOutputStream();71                 ContentStreamWriter tokenWriter = new ContentStreamWriter(out);72                 tokenWriter.writeTokens( tokens );73                 page.setContents( updatedStream );74             }75             doc.save( outputFile );76         }77         finally78         {79             if( doc != null )80             {81                 doc.close();82             }83         }84     }

4、在PDF中加入图片:

 1 /** 2      * Add an image to an existing PDF document. 3      * 4      * @param inputFile The input PDF to add the image to. 5      * @param image The filename of the image to put in the PDF. 6      * @param outputFile The file to write to the pdf to. 7      * 8      * @throws IOException If there is an error writing the data. 9      * @throws COSVisitorException If there is an error writing the PDF.10      */11     public void createPDFFromImage( String inputFile, String image, String outputFile ) 12         throws IOException, COSVisitorException13     {14         // the document15         PDDocument doc = null;16         try17         {18             doc = PDDocument.load( inputFile );19 20             //we will add the image to the first page.21             PDPage page = (PDPage)doc.getDocumentCatalog().getAllPages().get( 0 );22 23             PDXObjectImage ximage = null;24             if( image.toLowerCase().endsWith( ".jpg" ) )25             {26                 ximage = new PDJpeg(doc, new FileInputStream( image ) );27             }28             else if (image.toLowerCase().endsWith(".tif") || image.toLowerCase().endsWith(".tiff"))29             {30                 ximage = new PDCcitt(doc, new RandomaccessFile(new File(image),"r"));31             }32             else33             {34                 BufferedImage awtImage = ImageIO.read( new File( image ) );35                 ximage = new PDPixelMap(doc, awtImage);36             }37             PDPageContentStream contentStream = new PDPageContentStream(doc, page, true, true);38 39             //contentStream.drawImage(ximage, 20, 20 );40             // better method inspired by http://stackoverflow.com/a/22318681/53564641             float scale = 0.5f; // reduce this value if the image is too large42             System.out.println(ximage.getHeight());43             System.out.println(ximage.getWidth());44 //            ximage.setHeight(ximage.getHeight()/5);45 //            ximage.setWidth(ximage.getWidth()/5);46             contentStream.drawXObject(ximage, 20, 200, ximage.getWidth()*scale, ximage.getHeight()*scale);47 48             contentStream.close();49             doc.save( outputFile );50         }51         finally52         {53             if( doc != null )54             {55                 doc.close();56             }57         }58     }

5、PDF文件转换为图片:

 1 public void toImage() { 2     try { 3         PDDocument doc = PDDocument 4                 .load("F://java56班//eclipse-SDK-4.2-win32//pdfwithText.pdf"); 5         int pageCount = doc.getPageCount(); 6         System.out.println(pageCount); 7         List pages = doc.getDocumentCatalog().getAllPages(); 8         for (int i = 0; i < pages.size(); i++) { 9             PDPage page = (PDPage) pages.get(i);10             BufferedImage image = page.convertToImage();11             Iterator iter = ImageIO.getImageWritersBySuffix("jpg");12             ImageWriter writer = (ImageWriter) iter.next();13             File outFile = new File("F://java56班//eclipse-SDK-4.2-win32//"14                     + i + ".jpg");15             FileOutputStream out = new FileOutputStream(outFile);16             ImageOutputStream outImage = ImageIO17                     .createImageOutputStream(out);18             writer.setOutput(outImage);19             writer.write(new IIOImage(image, null, null));20         }21         doc.close();22         System.out.println("over");23     } catch (FileNotFoundException e) {24         // TODO Auto-generated catch block25         e.printStackTrace();26     } catch (IOException e) {27         // TODO Auto-generated catch block28         e.printStackTrace();29     }30 }

 

6、图片转换为PDF文件(支持多张图片转换为PDF文件):

 1 /** 2      * create the second sample document from the PDF file format specification. 3      *  4      * @param file 5      *            The file to write the PDF to. 6      * @param image 7      *            The filename of the image to put in the PDF. 8      *  9      * @throws IOException10      *             If there is an error writing the data.11      * @throws COSVisitorException12      *             If there is an error writing the PDF.13      */14     public void createPDFFromImage(String file, String image)throws IOException, COSVisitorException {15         // 多张图片转换为PDF文件16         PDDocument doc = null;17         doc = new PDDocument();18         PDPage page = null;19         PDXObjectImage ximage = null;20         PDPageContentStream contentStream = null;21 22         File files = new File(image);23         String[] a = files.list();24         for (String string : a) {25             if (string.toLowerCase().endsWith(".jpg")) {26                 String temp = image + "//" + string;27                 ximage = new PDJpeg(doc, new FileInputStream(temp));28                 page = new PDPage();29                 doc.addPage(page);30                 contentStream = new PDPageContentStream(doc, page);31                 float scale = 0.5f;32                 contentStream.drawXObject(ximage, 20, 400, ximage.getWidth()33                         * scale, ximage.getHeight() * scale);34                 35                 PDFont font = PDType1Font.HELVETICA_BOLD;36                 contentStream.beginText();37                 contentStream.setFont(font, 12);38                 contentStream.moveTextPositionByAmount(100, 700);39                 contentStream.drawString("Hello");40                 contentStream.endText();41                 42                 contentStream.close();43             }44         }45         doc.save(file);46         doc.close();47     }

7、替换PDF文件中的某个字符串:

 1  /** 2      * Locate a string in a PDF and replace it with a new string. 3      * 4      * @param inputFile The PDF to open. 5      * @param outputFile The PDF to write to. 6      * @param strToFind The string to find in the PDF document. 7      * @param message The message to write in the file. 8      * 9      * @throws IOException If there is an error writing the data.10      * @throws COSVisitorException If there is an error writing the PDF.11      */12     public void doIt( String inputFile, String outputFile, String strToFind, String message)13         throws IOException, COSVisitorException14     {15         // the document16         PDDocument doc = null;17         try18         {19             doc = PDDocument.load( inputFile );20 //            PDFTextStripper stripper=new PDFTextStripper("ISO-8859-1");21             List pages = doc.getDocumentCatalog().getAllPages();22             for( int i=0; i<pages.size(); i++ )23             {24                 PDPage page = (PDPage)pages.get( i );25                 PDStream contents = page.getContents();26                 PDFStreamParser parser = new PDFStreamParser(contents.getStream() );27                 parser.parse();28                 List tokens = parser.getTokens();29                 for( int j=0; j<tokens.size(); j++ )30                 {31                     Object next = tokens.get( j );32                     if( next instanceof PDFOperator )33                     {34                         PDFOperator op = (PDFOperator)next;35                         //Tj and TJ are the two operators that display36                         //strings in a PDF37                         if( op.getOperation().equals( "Tj" ) )38                         {39                             //Tj takes one operator and that is the string40                             //to display so lets update that operator41                             COSString previous = (COSString)tokens.get( j-1 );42                             String string = previous.getString();43                             string = string.replaceFirst( strToFind, message );44                             System.out.println(string);45                             System.out.println(string.getBytes("GBK"));46                             previous.reset();47                             previous.append( string.getBytes("GBK") );48                         }49                         else if( op.getOperation().equals( "TJ" ) )50                         {51                             COSArray previous = (COSArray)tokens.get( j-1 );52                             for( int k=0; k<previous.size(); k++ )53                             {54                                 Object arrElement = previous.getObject( k );55                                 if( arrElement instanceof COSString )56                                 {57                                     COSString cosString = (COSString)arrElement;58                                     String string = cosString.getString();59                                     string = string.replaceFirst( strToFind, message );60                                     cosString.reset();61                                     cosString.append( string.getBytes("GBK") );62                                 }63                             }64                         }65                     }66                 }67                 //now that the tokens are updated we will replace the68                 //page content stream.69                 PDStream updatedStream = new PDStream(doc);70                 OutputStream out = updatedStream.createOutputStream();71                 ContentStreamWriter tokenWriter = new ContentStreamWriter(out);72                 tokenWriter.writeTokens( tokens );73                 page.setContents( updatedStream );74             }75             doc.save( outputFile );76         }77         finally78         {79             if( doc != null )80             {81                 doc.close();82             }83         }84     }

 

上述描述的只是PDFBox的部分功能,在原始资源包中有很对例子,大家可以学习,PDFBox API路径:http://pdfbox.apache.org/docs/1.8.8/javadocs/

转载自:爱编程w2bc.com
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