YES you can update SP Stack on ABAP & JAVA Stack independently on Solution Manager 7.1
Use SUM tool for updating the Java stack & transaction SPAM/SAINT for updating the ABAP stack.
This feature available for SAP Solution Manager Only
Note: SUM supports this scenario for the Java stack but requires a special command on startup.
Detailed information is available in the Release Information Notes for SP Stacks of SAP Solution Manager, which are listed in SAP Note 1595736.
tags: SP Stack upgrade without using SUM,