java实现在线预览 - -之poi实现word、excel、ppt转html

简介

java实现在线预览功能是一个大家在工作中也许会遇到的需求，如果公司有钱，直接使用付费的第三方软件或者云在线预览服务就可以了，例如永中office、office web 365(http://www.officeweb365.com/)他们都有云在线预览服务，就是要钱0.0
如果想要免费的，可以用openoffice，还需要借助其他的工具(例如swfTools、FlexPaper等)才行，可参考这篇文章http://blog.csdn.net/z69183787/article/details/17468039，写的挺细的，实现原理就是：
1.通过第三方工具openoffice，将word、excel、ppt、txt等文件转换为pdf文件；
2.通过swfTools将pdf文件转换成swf格式的文件；
3.通过FlexPaper文档组件在页面上进行展示。
当然如果装了Adobe Reader XI，那把pdf直接拖到浏览器页面就可以直接打开预览，这样就不需要步骤2、3了，前提就是客户装了Adobe Reader XI这个pdf阅读器。
我这里介绍通过poi实现word、excel、ppt转html，这样就可以放在页面上了。

jar包链接: https://pan.baidu.com/s/13o2CZTwM-Igx6wcoyEu_ug 密码: n95q

word转html

package wordToHtml;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.InputStream;

import java.util.List;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.transform.OutputKeys;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.stream.StreamResult;

import org.apache.commons.io.FileUtils;

import org.apache.poi.hwpf.HWPFDocument;

import org.apache.poi.hwpf.converter.PicturesManager;

import org.apache.poi.hwpf.converter.WordToHtmlConverter;

import org.apache.poi.hwpf.usermodel.Picture;

import org.apache.poi.hwpf.usermodel.PictureType;

import org.w3c.dom.Document;

public class PoiWordToHtml {

 public static void main(String[] args) throws Throwable {

  final String path = "D:\\poi-test\\wordToHtml\\";

  final String file = "人员选择系分.doc";

  InputStream input = new FileInputStream(path + file);

  HWPFDocument wordDocument = new HWPFDocument(input);

  WordToHtmlConverter wordToHtmlConverter = new WordToHtmlConverter(

    DocumentBuilderFactory.newInstance().newDocumentBuilder()

      .newDocument());

  wordToHtmlConverter.setPicturesManager(new PicturesManager() {

   public String savePicture(byte[] content, PictureType pictureType,

     String suggestedName, float widthInches, float heightInches) {

    return suggestedName;

   }

  });

  wordToHtmlConverter.processDocument(wordDocument);

  List pics = wordDocument.getPicturesTable().getAllPictures();

  if (pics != null) {

   for (int i = 0; i < pics.size(); i++) {

    Picture pic = (Picture) pics.get(i);

    try {

     pic.writeImageContent(new FileOutputStream(path

       + pic.suggestFullFileName()));

    } catch (FileNotFoundException e) {

     e.printStackTrace();

    }

   }

  }

  Document htmlDocument = wordToHtmlConverter.getDocument();

  ByteArrayOutputStream outStream = new ByteArrayOutputStream();

  DOMSource domSource = new DOMSource(htmlDocument);

  StreamResult streamResult = new StreamResult(outStream);

  TransformerFactory tf = TransformerFactory.newInstance();

  Transformer serializer = tf.newTransformer();

  serializer.setOutputProperty(OutputKeys.ENCODING, "utf-8");

  serializer.setOutputProperty(OutputKeys.INDENT, "yes");

  serializer.setOutputProperty(OutputKeys.METHOD, "html");

  serializer.transform(domSource, streamResult);

  outStream.close();

  String content = new String(outStream.toByteArray());

  FileUtils.writeStringToFile(new File(path, "人员选择系分.html"), content, "utf-8");

 }

}

excel转html

package excelToHtml;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;

import java.io.InputStream;

import java.util.List;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.transform.OutputKeys;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.stream.StreamResult;

import org.apache.commons.io.FileUtils;

import org.apache.poi.hssf.converter.ExcelToHtmlConverter;

import org.apache.poi.hssf.usermodel.HSSFWorkbook;

import org.apache.poi.hwpf.converter.PicturesManager;

import org.apache.poi.hwpf.converter.WordToHtmlConverter;

import org.apache.poi.hwpf.usermodel.Picture;

import org.apache.poi.hwpf.usermodel.PictureType;

import org.w3c.dom.Document;

public class PoiExcelToHtml {

    final static String path = "D:\\poi-test\\excelToHtml\\";

     final static String file = "exportExcel.xls";

 public static void main(String args[]) throws Exception {

     InputStream input=new FileInputStream(path+file);

     HSSFWorkbook excelBook=new HSSFWorkbook(input);

     ExcelToHtmlConverter excelToHtmlConverter = new ExcelToHtmlConverter (DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument() );

     excelToHtmlConverter.processWorkbook(excelBook);

     List pics = excelBook.getAllPictures();

     if (pics != null) {

         for (int i = 0; i < pics.size(); i++) {

             Picture pic = (Picture) pics.get (i);

             try {

                 pic.writeImageContent (new FileOutputStream (path + pic.suggestFullFileName() ) );

             } catch (FileNotFoundException e) {

                 e.printStackTrace();

             }

         }

     }

     Document htmlDocument =excelToHtmlConverter.getDocument();

     ByteArrayOutputStream outStream = new ByteArrayOutputStream();

     DOMSource domSource = new DOMSource (htmlDocument);

     StreamResult streamResult = new StreamResult (outStream);

     TransformerFactory tf = TransformerFactory.newInstance();

     Transformer serializer = tf.newTransformer();

     serializer.setOutputProperty (OutputKeys.ENCODING, "utf-8");

     serializer.setOutputProperty (OutputKeys.INDENT, "yes");

     serializer.setOutputProperty (OutputKeys.METHOD, "html");

     serializer.transform (domSource, streamResult);

     outStream.close();

     String content = new String (outStream.toByteArray() );

     FileUtils.writeStringToFile(new File (path, "exportExcel.html"), content, "utf-8");

 }

}

ppt转html

其实只是ppt转图片，有了图片后放到页面上去，点击下一页就一张张显示就可以了。这里只介绍ppt转图片的过程。

package pptToImg;

import java.awt.Dimension;

import java.io.File;

import java.io.FileInputStream;

import java.io.FileNotFoundException;

import java.io.FileOutputStream;

import java.io.IOException;   

import java.awt.Color;

import java.awt.Dimension;

import java.awt.Graphics2D;

import java.awt.geom.Rectangle2D;

import java.awt.image.BufferedImage;   

import org.apache.poi.hslf.model.TextRun;

import org.apache.poi.hslf.record.Slide;

import org.apache.poi.hslf.usermodel.RichTextRun;

import org.apache.poi.hslf.usermodel.SlideShow;   

public class PPTtoImage {

    public static void main(String[] args) {

        // 读入PPT文件

        File file = new File("D:/poi-test/pptToImg/test.ppt");

        doPPTtoImage(file);

    }   

    public static boolean doPPTtoImage(File file) {

        boolean isppt = checkFile(file);

        if (!isppt) {

            System.out.println("The image you specify don't exit!");

            return false;

        }

        try {   

            FileInputStream is = new FileInputStream(file);

            SlideShow ppt = new SlideShow(is);

            is.close();

            Dimension pgsize = ppt.getPageSize();

            org.apache.poi.hslf.model.Slide[] slide = ppt.getSlides();

            for (int i = 0; i < slide.length; i++) {

                System.out.print("第" + i + "页。");   

                TextRun[] truns = slide[i].getTextRuns();

                for ( int k=0;k<truns.length;k++){

                   RichTextRun[] rtruns = truns[k].getRichTextRuns();

                  for(int l=0;l<rtruns.length;l++){

                       int index = rtruns[l].getFontIndex();

                        String name = rtruns[l].getFontName();

                        rtruns[l].setFontIndex(1);

                        rtruns[l].setFontName("宋体");

//                        System.out.println(rtruns[l].getText());

                   }

                }

                BufferedImage img = new BufferedImage(pgsize.width,pgsize.height, BufferedImage.TYPE_INT_RGB);   

                Graphics2D graphics = img.createGraphics();

                graphics.setPaint(Color.BLUE);

                graphics.fill(new Rectangle2D.Float(0, 0, pgsize.width, pgsize.height));

                slide[i].draw(graphics);   

                // 这里设置图片的存放路径和图片的格式(jpeg,png,bmp等等),注意生成文件路径

                FileOutputStream out = new FileOutputStream("D:/poi-test/pptToImg/pict_"+ (i + 1) + ".jpeg");

                javax.imageio.ImageIO.write(img, "jpeg", out);

                out.close();   

            }

            System.out.println("success!!");

            return true;

        } catch (FileNotFoundException e) {

            System.out.println(e);

            // System.out.println("Can't find the image!");

        } catch (IOException e) {

        }

        return false;

    }   

    // function 检查文件是否为PPT

    public static boolean checkFile(File file) {   

        boolean isppt = false;

        String filename = file.getName();

        String suffixname = null;

        if (filename != null && filename.indexOf(".") != -1) {

            suffixname = filename.substring(filename.indexOf("."));

            if (suffixname.equals(".ppt")) {

                isppt = true;

            }

            return isppt;

        } else {

            return isppt;

        }

    }   

}


ppt转图片有个缺陷，就是ppt里不是宋体的字有些可能会变成框框。 

以上都需要引入poi的jar包。 

要实现在线预览，只需把转换得到的html在新标签页打开或者镶嵌到某块区域就可以展现了。