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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