All my ptrap looked like the one you showed me, when I lived in NC. But in MA it may not be allowed. I found some poster has commented:
"in massachusetts, it is illegal to have a slip joint on the outlet side of the trap. however,if the p-trap is not the removable type, it must have a clean out plug in the bottom."
Come to think of it, I don't think I have seen jbend style ptraps in local Lowes. Explains why all the rest of the bathrooms and kitchen is all glued.
Does that mean I have to replicate what I have now, but substitute glued trap portion with threaded? I can't find any info on what goes inside that joint, some compression washer, Teflon, putty, or it's self seating.