question: public void clean ( ObjID [ ] ids , long sequenceNum , VMID vmid , boolean strong ) { for ( ObjID id : ids ) { if ( dgcLog . isLoggable ( Log . VERBOSE ) ) { dgcLog . log ( Log . VERBOSE , "id = " + id + ", vmid = " + vmid + ", strong = " + strong ) ; } ObjectTable . unreferenced ( id , sequenceNum , vmid , strong ) ; } }
target:  The clean call removes the VMID from the set of clients that hold references to the object associated with the LiveRef ref.  The sequence number is used to detect late clean calls.  If the argument "strong" is true, then the clean call is a result of a failed "dirty" call, thus the sequence number for the VMID needs to be remembered until the client goes away.