Is there development demo code available using Java and some advice what libraries are best to use the REST API and to extract the data?
For a deeper look into our DataScope Select SOAP API, look into:
Overview | Quickstart | Documentation | Downloads | Tutorials
Is there development demo code available using Java and some advice what libraries are best to use the REST API and to extract the data?
Yes we have a whole set of Java demo code samples, available in the downloads section of the developer portal. They use popular public domain libraries to handle communication over HTTP and JSON content.