Using ActiveJDBC with multiple threads

Question

I have an application that is built on ActiveJDBC for Database interactions. I'm now in the process of multithreading the thing but I'm running into a couple issues.

Whenever I try to get an object from the DB, I get this exception: Cannot open a new connection because existing connection is still on current thread, dbName: default, connection instance: com.mchange.v2.c3p0.impl.NewProxyConnection@75412c2f. This might indicate a logical error in your application.

Note it says com.mchange.v2.c3p0.impl.NewProxyConnection. This is so because I already tried to use DataSources but that didn't either. Could somebody point me to the track or suggest an alternative (threadsafe) to Active JDBC?

Thanks.

I use this http://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/jdbc.html but i'm really sure that activeJDBC is safe with multiple threads..I hope it helps. If you don't use datasource be careful with transactions and open/close connection. — ZaoTaoBao, Apr 23 '14 at 14:54
i only found an example, sure that you have seen https://github.com/florinpatrascu/micro-examples/tree/master/micro-aj explain min/max threads for jetty. srry. — ZaoTaoBao, Apr 23 '14 at 15:26

score 4 · Accepted Answer · answered Apr 23 '14 at 19:14

4

The error message you are getting is quite explanatory. Connection was not closed. ActiveJDBC is certainly thread-safe, as we built quite a number of projects with it. However ActiveJDBC attaches a connection to a current thread with Base.open() method and removes it from this thread using Base.close() method. I think you are forgetting to do the latter. Please see this to understand more: http://javalite.io/database_connection_management

answered Apr 23 '14 at 19:14

ipolevoy

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I did close the connection but the problem is, multiple threads can interact with the db at the same time. – Martijn Apr 23 '14 at 19:14
you need to call Base.close() - this removes the connection from current thread and closes it at the same time – ipolevoy Apr 23 '14 at 19:15
yes, each connection will live on a thread until removed from thread and closed – ipolevoy Apr 23 '14 at 20:07
Ok, why do I get the message that it was not closed then? I don't understand that part... – Martijn Apr 23 '14 at 20:24
probably because you did not call Base.close() – ipolevoy Apr 23 '14 at 21:18

Using ActiveJDBC with multiple threads

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