is is possible to use C3P0 with GoogleSQL?

[Pascal Voitot Dev]

Hello,
I'm trying to plug a C3P0 pooled datasource on GoogleSQL.
Due to the GAE/JRE class whitelist, I'm stuck with missing classes...
The main one is:

java.lang.NoClassDefFoundError: javax/naming/NamingException


Is it simply impossible to use C3P0 with GoogleSQL/GAE or is there a work-around?

If it's impossible to use C3P0, what do you advise to replace it and get a datasource and not only a conection as explained in the doc? (BasicDataSource?)


thanks in advance
Pascal

[Rob Clevenger]

I've heard others have success with Apache DBCP,  however I don't think a connection pool is required. The time to check a connection for validity should be close to the time to open a new connection.

If you do use one, make sure the connection is valid before using one from the pool (using Connection.isValid() or a simple query, like "DO 1")

Rob

[Pascal Voitot Dev]

I'll try that...
The connection model is not really clear in the doc.
Apparently this is MySQL but it's a GAE JDBC Driver so we don't really know what this driver does or not...
How does it work? One connection per GAE instance or something like that?

Thanks
Pascal

[Rob Clevenger]

You don't want to share it across requests, I typically open  the connection at the beginning of a request and close it at the end.

Rob

[Pascal Voitot Dev]

On Thu, Nov 3, 2011 at 2:47 PM, Rob Clevenger <rcle...@google.com> wrote:

You don't want to share it across requests, I typically open  the connection at the beginning of a request and close it at the end.

Yes this is a good manner in a stateless world :)
Anyway, I'm trying to plug GoogleSQL to Play+Siena and I try to modify the least possible! Play uses C3P0 ComboPooledDatasource and C3P0 requires NamingException :(. So I'll try to plug Apache DBCP instead of that...

Pascal
 

[javabuddy]

I tried datanucleus + DBCP but no luck. Let me know if you find
anything different.

On Nov 3, 8:53 am, Pascal Voitot Dev <pascal.voitot....@gmail.com>
wrote:

> On Thu, Nov 3, 2011 at 2:47 PM, Rob Clevenger <rclev...@google.com> wrote:
> > You don't want to share it across requests, I typically open  the
> > connection at the beginning of a request and close it at the end.
>
> Yes this is a good manner in a stateless world :)
> Anyway, I'm trying to plug GoogleSQL to Play+Siena and I try to modify the
> least possible! Play uses C3P0 ComboPooledDatasource and C3P0 requires
> NamingException :(. So I'll try to plug Apache DBCP instead of that...
>
> Pascal
>
>
>
>
>
>
>
> > Rob
>
> > On Thu, Nov 3, 2011 at 6:46 AM, Pascal Voitot Dev <
> > pascal.voitot....@gmail.com> wrote:
>
> >> I'll try that...
> >> The connection model is not really clear in the doc.
> >> Apparently this is MySQL but it's a GAE JDBC Driver so we don't really
> >> know what this driver does or not...
> >> How does it work? One connection per GAE instance or something like that?
>
> >> Thanks
> >> Pascal
>

[Pascal Voitot Dev]

Ok I have some success (DDL works, tables are created) but now i have this weird error when trying to insert rows.
Siena creates a preparedstatement with a few parameters and when calling preparedstatement.setObject, it gives a NPE.

Caused by: java.lang.NullPointerException
	at com.google.cloud.sql.jdbc.PreparedStatement.setObject(PreparedStatement.java:407)
	at org.apache.commons.dbcp.DelegatingPreparedStatement.setObject(DelegatingPreparedStatement.java:165)
	at siena.jdbc.JdbcPersistenceManager.setParameter(JdbcPersistenceManager.java:420)

To be noted that this exact code works perfectly with MySQL/Postgres naturally. 

Before using mass debugging weapons, do you see any reason why a preparedstatement couldn't work there?

Thanks
Pascal