java在线预览txt、word、ppt、execel，pdf代码

在页面上显示各种文档中的内容。在servlet中的逻辑

word：

BufferedInputStream bis = null;
URL url = null;
HttpURLConnection httpUrl = null; // 建立链接
url = new URL(urlReal);
httpUrl = (HttpURLConnection) url.openConnection();// 连接指定的资源
httpUrl.connect();// 获取网络输入流
bis = new BufferedInputStream(httpUrl.getInputStream());

String bodyText = null;
WordExtractor ex = new WordExtractor(bis);
bodyText = ex.getText();
response.getWriter().write(bodyText);

excel：

BufferedInputStream bis = null;
URL url = null;
HttpURLConnection httpUrl = null; // 建立链接
url = new URL(urlReal);
httpUrl = (HttpURLConnection) url.openConnection();// 连接指定的资源
httpUrl.connect();// 获取网络输入流
bis = new BufferedInputStream(httpUrl.getInputStream());

content = new StringBuffer();
HSSFWorkbook workbook = new HSSFWorkbook(bis);
for (int numSheets = 0; numSheets < workbook.getNumberOfSheets(); numSheets++) {
HSSFSheet aSheet = workbook.getSheetAt(numSheets);// 获得一个sheet
content.append("/n");
if (null == aSheet) {
continue;
}
for (int rowNum = 0; rowNum <= aSheet.getLastRowNum(); rowNum++) {
content.append("/n");
HSSFRow aRow = aSheet.getRow(rowNum);
if (null == aRow) {
continue;
}
for (short cellNum = 0; cellNum <= aRow.getLastCellNum(); cellNum++) {
HSSFCell aCell = aRow.getCell(cellNum);
if (null == aCell) {
continue;
}
if (aCell.getCellType() == HSSFCell.CELL_TYPE_STRING) {
content.append(aCell.getRichStringCellValue()
.getString());
} else if (aCell.getCellType() == HSSFCell.CELL_TYPE_NUMERIC) {
boolean b = HSSFDateUtil.isCellDateFormatted(aCell);
if (b) {
Date date = aCell.getDateCellValue();
SimpleDateFormat df = new SimpleDateFormat(
"yyyy-MM-dd");
content.append(df.format(date));
}
}
}
}
}
response.getWriter().write(content.toString());

ppt：

BufferedInputStream bis = null;
URL url = null;
HttpURLConnection httpUrl = null; // 建立链接
url = new URL(urlReal);
httpUrl = (HttpURLConnection) url.openConnection();// 连接指定的资源
httpUrl.connect();// 获取网络输入流
bis = new BufferedInputStream(httpUrl.getInputStream());

StringBuffer content = new StringBuffer("");
SlideShow ss = new SlideShow(new HSLFSlideShow(bis));
Slide[] slides = ss.getSlides();
for (int i = 0; i < slides.length; i++) {
TextRun[] t = slides[i].getTextRuns();
for (int j = 0; j < t.length; j++) {
content.append(t[j].getText());
}
content.append(slides[i].getTitle());
}
response.getWriter().write(content.toString());

pdf：

BufferedInputStream bis = null;
URL url = null;
HttpURLConnection httpUrl = null; // 建立链接
url = new URL(urlReal);
httpUrl = (HttpURLConnection) url.openConnection();// 连接指定的资源
httpUrl.connect();// 获取网络输入流
bis = new BufferedInputStream(httpUrl.getInputStream());

PDDocument pdfdocument = null;
PDFParser parser = new PDFParser(bis);
parser.parse();
pdfdocument = parser.getPDDocument();
ByteArrayOutputStream out = new ByteArrayOutputStream();
OutputStreamWriter writer = new OutputStreamWriter(out);
PDFTextStripper stripper = new PDFTextStripper();
stripper.writeText(pdfdocument.getDocument(),writer);
writer.close();
byte[] contents = out.toByteArray();

String ts = new String(contents);
response.getWriter().write(ts);

txt：

BufferedReader bis = null;
URL url = null;
HttpURLConnection httpUrl = null; // 建立链接
url = new URL(urlReal);
httpUrl = (HttpURLConnection) url.openConnection();// 连接指定的资源
httpUrl.connect();// 获取网络输入流
bis = new BufferedReader( new InputStreamReader(httpUrl.getInputStream()));

StringBuffer buf=new StringBuffer();
String temp;
while ((temp = bis.readLine()) != null) {
buf.append(temp);
response.getWriter().write(temp);
if(buf.length()>=1000){
break;
}
}
bis.close();