I will convert your Excel data into one of several web-friendly formats, including HTML, JSON and XML.

Something that looks similar to Perl's Data::Dumper in Java.

XML serialization has a myriad of uses, including object persistence and data transport. However, some XML-serialization technologies can be complex to implement. XStream is a lightweight and easy-to-use open source Java™ library for serializing Java objects to XML and back again. Learn how to set up XStream, and discover how to use it to serialize and deserialize objects as well as to read configuration properties from an XML configuration file.

You can customize nXML mode so that / automatically inserts the rest of the end-tag when it occurs after ‘<’, by doing

M-x customize-variable RET nxml-slash-auto-complete-flag RET

and then following the instructions in the displayed buffer.