Hi Sebastian, I think it would be wiser to specify a validation query in the database repository descriptor to check if the connection is valid *each* time it is used. This will deal with not only the database being unavailable at startup, but throughout the operation of the application.
BTW, I suspect that the service method did nothing because your code did nothing that required opening a connection (i.e. opening a broker does not open a connection until it is needed). Also note that Brokers are pooled separately from Connections. Wally -----Original Message----- From: news [mailto:[EMAIL PROTECTED] On Behalf Of Sebastian Sent: Monday, May 03, 2004 10:31 AM To: [EMAIL PROTECTED] Subject: Re: How to test db connection on application startup I changed the code to obtain the connection from the serviceConnectionManager, but the problem remains, I can't catch the thrown java.sql.SQLException. Any ideas? try { pb = PersistenceBrokerFactory.defaultPersistenceBroker(); pb.serviceConnectionManager().getConnection(); } catch (Exception e) { throw new DatabaseOpenException(e); } Sebastian wrote: > Hi, > > when launching my ojb app I'd like to test if the db connection is > available. I thought I can do something like this: > > try > { > pb = PersistenceBrokerFactory.defaultPersistenceBroker(); > pb.beginTransaction(); > pb.commitTransaction(); > } > catch (Exception e) > { > throw new DatabaseOpenException(e); > } > > When launching the app with turned off db I get exception stacktrace > appended to the end of this post, but the SQLException is actually not > catched by my catch block. I guess that is because opening the db > connection is done in a separate thread? > > My question is, what is the best generic way to test the db connection > when launching an ojb enabled app? > > java.sql.SQLException: Unable to connect to any hosts due to > exception: > java.net.ConnectException: Connection refused: connect > at com.mysql.jdbc.Connection.createNewIO(Connection.java:1797) > at com.mysql.jdbc.Connection.<init>(Connection.java:562) > at > com.mysql.jdbc.NonRegisteringDriver.connect(NonRegisteringDriver.java:36 1) > at java.sql.DriverManager.getConnection(Unknown Source) > at java.sql.DriverManager.getConnection(Unknown Source) > at > org.apache.ojb.broker.accesslayer.ConnectionFactoryAbstractImpl.newConne ctionFromDriverManager(Unknown > Source) > at > org.apache.ojb.broker.accesslayer.ConnectionFactoryPooledImpl$ConPoolFac tory.makeObject(Unknown > Source) > at > org.apache.commons.pool.impl.GenericObjectPool.borrowObject(GenericObjec tPool.java:816) > > at > org.apache.ojb.broker.accesslayer.ConnectionFactoryPooledImpl.getConnect ionFromPool(Unknown > Source) > at > org.apache.ojb.broker.accesslayer.ConnectionFactoryAbstractImpl.lookupCo nnection(Unknown > Source) > at > org.apache.ojb.broker.accesslayer.ConnectionManagerImpl.getConnection(Un known > Source) > at > org.apache.ojb.broker.accesslayer.ConnectionManagerImpl.localBegin(Unkno wn > Source) > at > org.apache.ojb.broker.core.PersistenceBrokerImpl.beginTransaction(Unknow n > Source) > at > org.apache.ojb.broker.core.DelegatingPersistenceBroker.beginTransaction( Unknown > Source) > at > org.apache.ojb.broker.core.DelegatingPersistenceBroker.beginTransaction( Unknown > Source) > at test.DBTest.<init>(DBTest.java:26) --------------------------------------------------------------------- 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]
