Hi, > > Hello, > > OK! It is a bit clearer for me, thanks. > Each time I want to use a broker I should do: > > broker = PersistenceBrokerFactory.defaultPersistenceBroker(); > //I use the broker > broker.close();
Yes, this is the way it should be done. > Is it better to do this EACH time I use the broker or ask for > a broker one time (when the application start) and close > after (all) the use? It is better to do it each time. If this is an "issue" for you, I suggest you look at using ODMG; it hides all broker usage from your application. > About the MAX number of broker in OJB.properties, is it a > good way to set this number to 100 or even 1000? > > Finally what is the exact meaning of this 2 log messages: > "Already created persistence broker instances: x"? > "Already created connections: 3 returning: ..."? I'm afraid I don't know precisely.. Cheers, Charles. > Thanks for your help > Sylvain > > > > > -----Message d'origine----- > De: Charles Anthony [mailto:[EMAIL PROTECTED] > Date: lundi, 27. octobre 2003 11:27 > À: 'OJB Users List' > Objet: RE: problem with PB instances creation > > > Hi, > > at line 27, you should repeat lines 9-13. > > At line 10 > PersistenceBrokerFactory.defaultPersistenceBroker() asks the pool > for a broker, creating one *if* *necessary*. > broker.close releases some resources from the broker, and returns the > broker to the pool. > > In other words, after you close the broker, you can no longer > use it. You > must get another broker. > > If you really need to know how many (active) brokers there > are in the pool, > you should be able to do > > PersistenceBrokerFactoryDefaultImpl factory = > (PersistenceBrokerFactoryDefaultImpl) > PersistenceBrokerFactoryFactory.instance(); > int brokersInPool = factory.activePersistenceBroker(); > > Cheers, > > Charles > > > -----Original Message----- > > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED] > > Sent: 27 October 2003 10:17 > > To: [EMAIL PROTECTED]; [EMAIL PROTECTED] > > Subject: RE: problem with PB instances creation > > > > > > Hello Thomas, > > > > Is there a way to check how many instances are contained in > the pool? > > > > You can find an example below. > > You create a broker instance in line 10, right? > > You use the broker instance first time in line 19. After this > > use you close() the instance. > > But the problem is if you do the close() in line 25 when you > > use the broker for the second time in line 29 you have a > > ConnectionNotInProgressException. > > > > Do I have to create a second broker? > > Or do I have to call a broker from the pool? How? > > > > Thanks for your help > > Sylvain > > > > > > 1 public class MyExample { > > 2 > > 3 private PersistenceBroker broker; > > 4 > > 5 public void test() { > > 6 /** > > 7 * Persistence Broker > > 8 */ > > 9 try { > > 10 broker = > > PersistenceBrokerFactory.defaultPersistenceBroker(); > > 11 } catch (Throwable t) { > > 12 t.printStackTrace(); > > 13 } > > 14 > > 15 Criteria crit = new Criteria(); > > 16 ... > > 17 > > 18 try { > > 19 broker.beginTransaction(); > > 20 //query 1... > > 21 broker.commitTransaction(); > > 22 } catch (Throwable t) { > > 23 broker.abortTransaction(); > > 24 } finally { > > 25 broker.close(); > > 26 } > > 27 > > 28 try { > > 29 broker.beginTransaction(); > > 30 //query 2... > > 31 broker.commitTransaction(); > > 32 } catch (Throwable t) { > > 33 broker.abortTransaction(); > > 34 } finally { > > 35 broker.close(); > > 36 } > > 37 } > > 38 } > > > > > > -----Message d'origine----- > > De: Thomas Mahler [mailto:[EMAIL PROTECTED] > > Date: vendredi, 24. octobre 2003 18:17 > > À: OJB Users List > > Objet: Re: problem with PB instances creation > > > > > > Hi Sylvain, > > > > [EMAIL PROTECTED] wrote: > > > Hello, > > > > > > I'm using OJB in my web application and I have some problem > > with PB instances creation. > > > > > > Each time I want to read/write data from/to my database I > > create a PB intance: > > > broker = PersistenceBrokerFactory.defaultPersistenceBroker(); > > > > > > The problem is that lot of PB instances are created and > > never destroyed. > > > I can see that in logs: "Already created persistence broker > > instances: x". > > > For that I close the broker instance each time: > > > broker.close(); > > > > > > But I have noticed that this function doesn't destroy the > > PB instance. > > > So what is the job of this function? > > > > broker instances are not destroyed, because it's expensive > to create > > them. Thus OJB is pooling broker instances. > > broker.close() simply makes the instances unavailable for > > further calls > > and puts the instance back to the pool. > > > > > How to destroy PB instance and prevent that the number of > > PB instances is equal to the maximum? > > > > If you close broker instancecs always after usage the number > > of active > > broker instances (i.e. brokers that are borrowed from the > > pool) equals > > the number servlet instances requesting a broker. > > > > You can change the broker pool behaviour through settings in > > OJB.properties: > > > > # specifies the behaviour of the pool when broker capacity is > > # exhausted (see maxActive above) > > # 0 - fail > > # 1 - block > > # 2 - grow > > whenExhaustedAction=0 > > > > The default setting is 0, so the pool throws an exception if > > an instance > > is requested when the pool is exhausted. > > By setting this value to 2 the pool would simply grow and a > > new broker > > instance. > > By setting it to 1 you can avoid growing of the pool, the > > application is > > blockes until an instance is available from the pool. > > > > cheers, > > Thomas > > > > > > > Thanks for any help > > > Sylvain > > > > > > > > > > > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > --------------------------------------------------------------------- > > To unsubscribe, e-mail: [EMAIL PROTECTED] > > For additional commands, e-mail: [EMAIL PROTECTED] > > > > > > > This email and any attachments are strictly confidential and > are intended > solely for the addressee. 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