Thanks Ari, yes, a polling mechanism with local caching and event notification on the client should work great. Might be a good cayenne 4 feature. I'll check out your app for inspiration :-) Congrats on the baby.
On Nov 18, 2007 3:52 PM, Aristedes Maniatis <[EMAIL PROTECTED]> wrote: > > On 19/11/2007, at 6:57 AM, Tarik wrote: > > > I have been trying the cayenne ROP features and am considering using > > it for > > a project which requires multiple (swing) clients to connect to an > > application server. I have got it to work for a simple example. > > Now I have > > some more design questions. > > We do much of what you describe in a client/server ROP application: > http://www.ish.com.au/oncourse > . You can download it and give it a try to see the user interface and > I guess there isn't technically much to stop you poking around its > class structure with a little decompiling :-) > > > - Can a client app register to listen for changes on server object? > > Since > > there will be multiple clients, I want changes made by one client to > > appear > > on the others without them having to refresh. > > There is a messaging framework in Cayenne, although in our case I've > been thinking of doing something a bit different since we may have > clients which aren't on the same subnet, so some sort of polling > mechansim was what I was planning. > > > - I will need to create a number of JTables with data coming from the > > server. Has anyone done some labor-saving work around automatically > > displaying cayenne object data in a JTable? (It would be awesome if it > > allowed traversing associations, adding /removing columns / applying > > filters, etc.) > > We have. Perhaps we could discuss this further off list. I am a bit > busy for the next 2-3 weeks what with a tender process, a large new > customer migration, oh, and the birth of my daughter last week... she > is very cute. > > > - What kind of locking does data context provide? say i have two > > threads > > updating an object and one commits first and stales the object. > > What will > > happen when the second thread tries to commit. > > - Is there a know throughput limit in terms of transactions per > > second with > > the hessian web service? > > No limit really since Hessian is just a lightweight serialiser. > Probably the limit is more in Jetty or whatever servlet container you > are running, or perhaps in your database backend. We don't scale our > application beyond about a dozen users, so our needs aren't huge. We > chose Jetty mainly for its support in version 6 for a high rate of > small transactions, plus it is very simple to use. > > Ari > > > > --------------------------> > ish > http://www.ish.com.au > Level 1, 30 Wilson Street Newtown 2042 Australia > phone +61 2 9550 5001 fax +61 2 9550 4001 > GPG fingerprint CBFB 84B4 738D 4E87 5E5C 5EFA EF6A 7D2E 3E49 102A > > >
