Need help on SunCertPathBuilderException:

Hi Team , 

Trying to make connection from clients network to api.box.com using java and getting exception
Caused by: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target

I went over a few threads on this forum, but wanted to clarify which certificates need to be deployed on client's machine?

Will it work if I deployed a self-signed certificate on the source machine?

Thanks