This launcher is only used to do a JDK installation. Actual build steps would be using the core RemoteLauncher instead. So I think this is invalid.
Jesse Glick JDK install was removed from the SSH build Agents plugin, Do it means that nobody uses it? I think that this class is not used also, what about remove it
Hah, indeed. https://github.com/jenkinsci/ssh-slaves-plugin/pull/179