Not enough info really.
It could be a few things, for example;
As per: https://answers.splunk.com/answers/67327/splunk-java-sdk-connection-to-splunk-failed.html
"Ensure that your connection credentials are correct, notably that you are using HTTPS over Port 8089 to your SplunkD Server.
As a guess, you might be trying to connect to SplunkWeb on port 8000, which is not where the REST endpoints are located."
As per: https://answers.splunk.com/answers/209379/no-appropriate-protocol-protocol-is-disabled-or-ci.html
"Splunk needs to release a new jar without SSLv3 hardwired (in HttpService.java) in order to make this work with the latest Java 8. Meanwhile you need to stick with Java 7 or build your own jar from the SDK package and use SSLv2 instead."
... View more