Server side application to convert XML into XLS format, with advanced formatting

I am looking for a binary or script that can run on a Linux Server, that is capable of converting XML file into an XLS spread she开发者_开发问答et. It must support Text/Cell formatting (bold/borders/alignment) as well as formulas.

There is NO GUI, this must be triggered by a call to the server. Available languages PHP, Python, Perl (Java possible but not preferred). Open source preferred but willing to pay for a binary package that supports all the options effectively.

So to put this in a simple question: Is there a binary application (or script) that can run on a server to convert XML into XLS (for web based clients to download) supporting a wide range of formatting options?

The ability to convert BACK (from XLS to XML) is very desirable.

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There exists a pure Java API to create, manipulate and read Microsoft Excel files: Apache POI. This works without a GUI on a Linux server. You only have to parse your XML file, extract the needed data and use POI to create the spreadsheet file.