For live file update.
Change this in
apache-tomcat-VERSION/conf/server.xml
<?xml version="1.0" encoding="UTF-8"?>
...
<Server port="8005" shutdown="SHUTDOWN">
...
<Service name="Catalina">
...
<Engine name="Catalina" defaultHost="localhost">
...
<Host name="localhost" appBase="webapps"
...
<Context docBase="E:\assets" path="/files" />
<!--Should be same on FileController & UploadDownloadController -->
</Host>
</Engine>
</Service>
</Server>