On 11.04.11 05:50, "Felix Meschberger" <[email protected]> wrote: >Am Freitag, den 08.04.2011, 12:04 +0100 schrieb Alexander Klimetschek: >> On 08.04.11 08:01, "Carsten Ziegeler" <[email protected]> wrote: >> >maps rarely have an order regardless of the language. >> >> A linked map is not an unusual data structure. As Tobi noted, WCM/CMS >>is a >> prominent use case. > >Yes, but: the Map interface itself has no defined order: "Some map >implementations, like the TreeMap class, make specific guarantees as to >their order; others, like the HashMap class, do not." > >So, if you encounter a "Map" (not a TreeMap or LinkedHashMap), you must >not depend on any key ordering ... > >And most Map implementations used are in fact neither TreeMap nor >LinkedHashMap.
Yes, I agree. However,this is "just" the way the abstractions in the Java Collections API have been designed. With "unusual data structure" I was actually meaning use-cases rather than specific data structure concepts in languages such as Java. For a protocol-level data structure you want to be language-independent, and focus on what is needed. Not sure if I wrote that already: it is really unfortunate that the order is excluded from JSON (which only comes from the ECMAscript definition) when the serialization format already keeps the ordering so easily. Regards, Alex -- Alexander Klimetschek Developer // Adobe (Day) // Berlin - Basel
