No.  Because of the way garbage collection works, the virtual machine
would need to basically traverse the entire object graph anyway just to
determine if that object is referenced from any other live objects.  If
that's the case, then you may as well free up all the other dead objects
at the same time.  To do otherwise would be like spending all day
cooking a seven course meal, then eating a biscuit and throwing the
remainder in the trash.

Wojtek Bok wrote On 10/30/06 12:17,:

   Probably not.  It would amount to having the program assert
"such-and-such object is garbage," an assertion the JVM would
need to verify before it could be acted upon.  (Consider the
consequences of collecting an object that did in fact have a
few live references still kicking around, whether through error
or through malice.)

   To verify that an object is truly garbage (or that it is not
non-garbage, which may be a better description of contemporary
collectors), the JVM would need to do pretty much the same
amount of work it would do for an ordinary GC.  It seems to me
that "trustworthy selective GC" would not offer much savings
over ordinary GC; TSGC would just complicate the JVM and might
even make ordinary GC slower by imposing extra bookkeeping.