Not sure, but I believe Excel reads csv (comma-separated value) files. You would have to print to a text file with commas separating the values, and make sure you import into an Excel workbook with the same format.
Put the data in a text file (comma-separated value) then open the file with Excel, this is the easy way. You can also call a servlet, iterate the list where you have the data and use the POI library (http://jakarta.apache.org/poi/), to bring the data in a file excel. Another way is to use the library DisplayTag in your jsp, this is a tag that display the data in a table, give it a list of objects and it will handle column display, sorting, paging, cropping, grouping, exporting, smart linking and decoration of a table in a customizable XHTML style. Take a look to this url http://displaytag.sourceforge.net/11/ http://displaytag.sourceforge.net/11/export.html