I have a machine (incidentally with Ubuntu Linux) reporting 2 devices by lpstat -v:
device for XEROX-WorkCentre-4250-_xxxx: ipps://stt-mac-13.local:631/printers/XEROX_WorkCentre_4250__xxxx_
device for Xerox_by_3031: socket://xx.xx.xx.xx:9100

Now, if I'm calling
PrintServiceLookup.lookupPrintServices(DocFlavor.SERVICE_FORMATTED.PAGEABLE, null)
I'm getting only one service (with the second printer). Apparently ipps: protocol is not supported in details so there's no attributes available.

What is more interesting, if I call
PrintServiceLookup.lookupPrintServices(null,null)
there are 3 services reported, not 2: an extra one for that ipps printer.

This is behavior of both jdk8 and 9: I cannot compile my test with 7 but expect perhaps the same after its adaptation.