Yes, I know. I just use generated object id to create unique file to archive object. I generate id by current date and time "yyyyMMddHHmmssSSS + object hash". But It is my mistake. Now I use "yyyyMMddHHmmssSSS + UUID" (I need date parameter too). And I think id like "yyyyMMddHHmmssSSS + object address" is good too for my purpose.
2011/9/23 Mariano Martinez Peck <[email protected]> > > > On Fri, Sep 23, 2011 at 3:22 PM, Denis Kudriashov <[email protected]>wrote: > >> I am sure I see It in some block bost. But dont remember >> >> > Ok, but GC can move objects arround. If you stick to that value as #hash > then you dictionaries will be screw...you would need a rehash. But you don't > know when to trigger it ;) > > > >> >> 2011/9/23 Mariano Martinez Peck <[email protected]> >> >>> >>> >>> On Fri, Sep 23, 2011 at 3:02 PM, Denis Kudriashov >>> <[email protected]>wrote: >>> >>>> Thank you for all your responses. I will use UUID. >>>> >>>> Another assumption: >>>> I know there is a trick to get object memory address. >>>> >>> >>> which one? >>> >>> >>>> Can it be used for object identity? (inside memory of objects) >>>> >>>> >>>> >>>> * >>>> * >>>> 2011/9/23 Marcus Denker <[email protected]> >>>> >>>>> >>>>> On Sep 23, 2011, at 1:08 PM, Denis Kudriashov wrote: >>>>> >>>>> > Hello, >>>>> > >>>>> > I use hash message to generate unique object id. (unique between >>>>> current memory objects). >>>>> > And I catch situation when two objects has same hash value. Objects >>>>> has been created in loop almost at same time. >>>>> > >>>>> > So my question - is it really possible? >>>>> >>>>> Yes, easily, as there are only 12 bits for the hash, there are only >>>>> 4096 different hash values. >>>>> >>>>> This means that a hash is *not* at all a UUID, and all hashing data >>>>> structures need to be optimized >>>>> for the case of hash collision, as it will happen a lot. >>>>> >>>>> Marcus >>>>> >>>>> >>>>> -- >>>>> Marcus Denker -- http://marcusdenker.de >>>>> >>>>> >>>>> >>>> >>> >>> >>> -- >>> Mariano >>> http://marianopeck.wordpress.com >>> >>> >> > > > -- > Mariano > http://marianopeck.wordpress.com > >
