Windows:
	javac -classpath jxl.jar MyClass.java
	java -classpath jxl.jar;. MyClass
Unix:
	javac -classpath jxl.jar MyClass.java
	java -classpath jxl.jar:. MyClass
Eclipse:
	Right click on your Project, Select Java Build Path, open Libraries tab,
	Add External JARs..., select jxl.jar

  for (int i = 0 ; i < numrows ; i++)
  {
    for (int j = 0 ; j < numcols ; j++)
    {
      readCell = sheet.getCell(i, j);
      newCell = readCell.copyTo(i, j);
      readFormat = readCell.getCellFormat();
      newFormat = new WritableCellFormat(readFormat);
      newCell.setCellFormat(newFormat);
      newSheet.add(newCell);
    }
  }

Most people assume that setting the HTTP Content-Type to "application/vnd.ms-excel" and/or using an extension of ".xls" for downloaded workbooks is enough. For most recent default installations of Office, Windows, and IE, it is enough. However, for some older installations of Office, Windows, and IE, many of us have seen that Excel still opens in a separate window (outside of IE).

The other thing which must be done is to edit the advanced MIME type settings on the Windows computers which will be hitting your web site. In other words, your customers must do this next step: there is nothing you can do from your response stream (or anywhere else on your web site) to enforce this advanced MIME setting.

The place where the MIME setting is changed varies from Windows version to version. I will give the directions for Windows 2000.

1. Open File Explorer
2. Goto the Tools/Folder Options menu
3. Open the File Types tab
4. Select the XLS (or XLT if using templates) registered file type and click "Advanced" button.
5. Make sure the "Browse in same window" checbox is CHECKED.
6. Click OK and Close.

That's it.

I remember older versions of Windows and/or IE made these settings available in IE, not File Explorer.

Make sure you still set the Content-Type of response streams to "application/vnd.ms-excel" and use an extension of ".xls" for downloaded files.

Thanks go out to Dermot Balson and the microsoft.public.excel.programming newsgroup.
http://groups.google.com/groups?selm=vsNn6.135791%24Z2.1839760%40nnrp1.uunet.ca

1. JExcelApi writes all strings in Unicode, whereas Excel will save strings as single-byte ASCII encoding when it can. This can halve the size of all stored strings.
2. If many cells use the same formula, Excel will only write this formula to the underlying file once, whereas JExcelApi writes the formula once for each cell.
3. If you write many blank cells sequentially, Excel groups these into a single MULBLANK record when saving, whereas JExcelApi writes individual records for each cell.

  WritableFont boldRedFont = new WritableFont(WritableFont.ARIAL, 10, WritableFont.BOLD); 	
  boldRed.setColour(Colour.RED);
  WritableCellFormat boldRed = new WritableCellFormat(boldRedFont);
  for (int row = 0; row<100; row++)
  {
    sheet.addCell(new Label(0,row,"Row "+row,boldRed);
  }

  WritableFont boldRedFont = new WritableFont(WritableFont.ARIAL, 10, WritableFont.BOLD); 	
  boldRed.setColour(Colour.RED);
  for (int row = 0; row<100; row++)
  {
    sheet.addCell(new Label(0,row,"Row "+row,new WritableCellFormat(boldRedFont));
  }

	<form name="frm" action="/servlet/MyServlet" method="post" enctype="multipart/form-data">
	<input type="file" name="fl_upload">
	<input type="submit" value="Upload">
	<input type="reset" value="cancel">
	</form>

		DiskFileUpload fu = new DiskFileUpload();
		fu.setSizeMax(MAX_SIZE);
		fu.setSizeThreshold(1024);
		fu.setRepositoryPath(System.getProperty("java.io.tmpdir"));
		List fileList = fu.parseRequest(request);
		InputStream uploadedFileStream = null;
		String uploadedFileName = null; // name of file on user's computer
		for (Iterator i = fileList.iterator(); i.hasNext(); )
		{
			FileItem fi = (FileItem)i.next();
			if (fi.isFormField())
			{
				String key = fi.getFieldName();
				String val = fi.getString();
				System.out.println("Form parameter " + key + "=" + val);
			} else
			{
				if (fi.getSize() < 1)
				{
					throw new Exception("No file was uplaoded");
				}
				uploadedFileName = fi.getName();
				uploadedFileStream = fi.getInputStream();
			}
		}

		Workbook workbook = Workbook.getWorkbook(uploadedFileStream);

	import java.io.IOException;
	import java.io.OutputStream;
	 
	import javax.servlet.ServletException;
	import javax.servlet.http.HttpServlet;
	import javax.servlet.http.HttpServletRequest;
	import javax.servlet.http.HttpServletResponse;
	 
	import jxl.Workbook;
	import jxl.write.Label;
	import jxl.write.WritableSheet;
	import jxl.write.WritableWorkbook;
	 
	public class Sample extends HttpServlet
	{
	 public void doGet(HttpServletRequest request, HttpServletResponse response)
	 throws ServletException, IOException
	 {
	  OutputStream out = null;
	  try
	  {
	   response.setContentType("application/vnd.ms-excel");
	   response.setHeader("Content-Disposition", "attachment; filename=sampleName.xls");
	   WritableWorkbook w = Workbook.createWorkbook(response.getOutputStream());
	   WritableSheet s = w.createSheet("Demo", 0);
	   s.addCell(new Label(0, 0, "Hello World"));
	   w.write();
	   w.close();
	  } catch (Exception e)
	  {
	   throw new ServletException("Exception in Excel Sample Servlet", e);
	  } finally
	  {
	   if (out != null)
	    out.close();
	  }
	 }
	}


		

	import java.awt.image.BufferedImage;
	import java.io.ByteArrayOutputStream;
	import javax.imageio.ImageIO;
....
	private static final double CELL_DEFAULT_HEIGHT = 17;
	private static final double CELL_DEFAULT_WIDTH = 64;
....
	File imageFile = new File(GIF_OR_JPG_IMAGE_FILE);
	BufferedImage input = ImageIO.read(imageFile);
	ByteArrayOutputStream baos = new ByteArrayOutputStream();
	ImageIO.write(input, "PNG", baos);
	sheet.addImage(new WritableImage(1,1,input.getWidth() / CELL_DEFAULT_WIDTH,
		input.getHeight() / CELL_DEFAULT_HEIGHT,baos.toByteArray()));

To figure out if JExcelAPI supports feature XXXXXX on a copy, perform a simple test:

1. Create a spreadsheet using feature XXXXXX
2. Run the command: java -jar jxl.jar -rw TestFile.xls CopiedFile.xls
3. Open up CopiedFile.xls in Excel and see if feature XXXXXX is still present

1. Try to figure out how to implement it yourself in the source code
2. Create an activation macro in your template that do feature XXXXXX for you

• Pivot Tables
• Dropdown Lists
• Rich Text in cells
• Set repeating rows
• Password Protection