Hi,
What server version are you working against? for a working example that should be fine at least with the latest and was also tested against Hercules [version 8], see:
https://github.com/kaltura/kaltura-chunked-upload-test
This should work well for you when using the clientlib code from here:
https://github.com/kaltura/KalturaGeneratedAPIClientsJava/archive/11.5.0.zip
or, using the Maven pre-build jar from here:
http://search.maven.org/#search|ga|1|kaltura
if it doesn't, please specify the exact errors you're seeing, along with any stack trace you may get.