This is a common task that comes up time and again. The solution can figured out from various forum posts but it takes a while to put everything together, especially the writing of the Excel file to the browser. This is a Utility class that takes a Table as input and exports a decent Excel file containing the data in the Container. It also handles HierarchicalContainers and the resulting Excel file will have the categories and subcategories properly grouped/outlined. There are a number of configurable properties. The user can specify a worksheet name, a report title, and an output file name. The user can also specify if there should be a Totals row at the bottom of the export. The user can pass in custom POI CellStyles. However, if none of these are specified, the user only needs to pass in a Table. This add-on requires the Apache POI library. The project currently uses poi-3.10-FINAL. This add-on requires the Apache Commons IO library (http://commons.apache.org/io/). The project uses v2.2. The reason for using this version is that it is also a Vaadin 7 dependency. This add-on uses Charles Anthony's solution from: http://vaadin.com/forum/-/message_boards/view_message/159583 The included icon comes from the fugue open source (Creative Commons) icon set.