Hi,
I faced similar issue when opening the java project on a fresh machine. Some of the jar files are not part of the sdk package. I manually added those jar files and then the project compiled and ran without any issues.
Open .classpath file @"C:\Program Files (x86)\SolarWinds\Orion SDK\Samples\JavaClient\" and check if all the jar files (with path) provided in the file are available in the respective directory.
Let us know if you do not have those jar files and need information on from where those files needs to be downloaded.
