項目需要在原有的PDF文件中插入圖片、文字,并將最終的PDF文件轉換為圖片,在網上找了很多Demo,現在開源可以解析處理PDF文件的第三方插件比較多,eg:IText、PDFBox等,現在就PDFBox解析處理PDF文件總結如下:
【PDFBox簡介】
自從Adobe公司1993年第一次發布公共PDF參考以來,支持各種語言和平臺的PDF工具和類庫就如雨后春筍般涌現。然而,java應用開發中Adobe技術的支持相對滯后了。這是個奇怪的現象,因為PDF文檔是企業信息系統存儲和交換信息的大勢所趨,而Java技術特別適合這種應用。然而,Java開發人員似乎直到最近才獲得成熟可用的PDF支持。 PDFBox(一個BSD許可下的源碼開放項目)是一個為開發人員讀取和創建PDF文檔而準備的純Java類庫。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過程十分簡單。加密/解密PDF文檔。從PDF和XFDF格式中導入或導出表單數據。向已有PDF文檔中追加內容。將一個PDF文檔切分為多個文檔。覆蓋PDF文檔。 PS:http://baike.baidu.com/link?url=TsYWHJtTPMhlf0UvKzPOk-j3f9KzF7morIa4CqoZ0s4yIDCLB3z8nLVgLHVz-AO4dE6S7ls_3_yuvXP03nLSiq最常見的一種PDF文本抽取工具就是PDFBox了,訪問網址http://pdfbox.apache.org/download.cgi,進入如下圖所示的下載界面。讀者可以在該網頁下載其最新的版本。本書采用的是pdfbox-1.8.8版本。PDFBox是一個開源的Java PDF庫,這個庫允許你訪問PDF文件的各項信息。在接下來的例子中,將演示如何使用PDFBox提供的API操作PDF文件。
【將剛下載的7個jar包引入到工程當中】
pdfbox-1.8.8-src.zip為pdfbox源代碼,里面有很對的例子,在pdfbox-1.8.8/examples目錄下存在
【以下為Demo正式開始】
1、創建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、讀取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(處理中文亂碼,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中加入圖片:
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文件轉換為圖片:
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、圖片轉換為PDF文件(支持多張圖片轉換為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 // 多張圖片轉換為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、替換PDF文件中的某個字符串:
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,在原始資源包中有很對例子,大家可以學習,PDFBox API路徑:http://pdfbox.apache.org/docs/1.8.8/javadocs/
轉載自:愛編程w2bc.com
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