Previewing the xls file in gwt

I need to preview the uploaded xls file in gwt which let the user to select th开发者_如何学运维e sheet. I want to preview all the sheets of the excel file uploaded by the user. I have no idea how I can approach and what controls I can use.

Please tell me the ways to perform the operation.

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By far the easiest would be to use Google Docs Viewer: https://docs.google.com/viewer

You can set it up in a few minutes. It also has embedded mode, so that you can embed it into your GWT page: http://googlesystem.blogspot.com/2009/09/embeddable-google-document-viewer.html