###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。
###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
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。