ExiProcessor
Command-line program for processing Efficient XML Interchange (EXI)
...The source code itself can also be used as an example of how to integrate EXIficient into existing Java XML libraries.
Command Line Examples:
Encode XML to EXI: java -jar ExiProcessor.jar -xml_in notebook.xml -exi_out notebook.exi
Decode EXI to XML file: java -jar ExiProcessor.jar -exi_in notebook.exi -xml_out notebook.decoded.xml
Decode EXI to XML on stdout: java -jar ExiProcessor.jar -exi_in notebook.exi