Which Oracle Thin Driver Classes are used at runtime ?

Question

Hi,
I am using Weblogic 6.1 sp1 on a WIN 2000 Professional Box and am trying to connect
to a Oracle 8.1.7 Database that is located on a Solaris Box. I am using the Oracle
Thin Driver (classes12.zip) supplied by Oracle.
The relevant portion of config.xml looks like this:
<JDBCConnectionPool DriverName="oracle.jdbc.driver.OracleDriver"
InitialCapacity="12" LoginDelaySeconds="1" MaxCapacity="24"
Name="xxxConnectionPool" Password="xxxxxxxx"
Properties="user=user123" Targets="xxxserver" URL="jdbc:oracle:thin:@1.2.3.4:1521:xxxx"/>
The start script for the Server includes a CLASSPATH variable that includes both
weblogic.jar and classes12.zip (in that order)
The Database access code is from a singleton that is deployed with the beans and
looks like :
Context ctx = new InitialContext();
Object o = ctx.lookup("resonateDataSource");
dataSource = (DataSource)o;
Connection con = dataSource.getConnection();
PreparedStatement ps = con.prepareStatement(sqlXXX);
The actual subclasses of DataSource, Connection, PreparedStatement that are called
at runtime are from weblogic jDriver classes like weblogic.jdbc.rmi.SerialPreparedStatement,
weblogic.jdbc.rmi.SerialConnection etc and not from oracle thin driver.
Is this expected ? Why arent the corresponding classes from the Oracle Thin Driver
loaded ?
Thanks,
Praveen

Answer 1

Praveen wrote:
Hi,
I am using Weblogic 6.1 sp1 on a WIN 2000 Professional Box and am trying to connect
to a Oracle 8.1.7 Database that is located on a Solaris Box. I am using the Oracle
Thin Driver (classes12.zip) supplied by Oracle.
The relevant portion of config.xml looks like this:
<JDBCConnectionPool DriverName="oracle.jdbc.driver.OracleDriver"
InitialCapacity="12" LoginDelaySeconds="1" MaxCapacity="24"
Name="xxxConnectionPool" Password="xxxxxxxx"
Properties="user=user123" Targets="xxxserver" URL="jdbc:oracle:thin:@1.2.3.4:1521:xxxx"/>
The start script for the Server includes a CLASSPATH variable that includes both
weblogic.jar and classes12.zip (in that order)Hi. You should have the oracle zip first. This is because our stuff also contains an oracle zip, but
it's
older than the latest, and you want yours to be used. Whatever is first in the classpath is what will
be used.
The Database access code is from a singleton that is deployed with the beans and
looks like :...
The actual subclasses of DataSource, Connection, PreparedStatement that are called
at runtime are from weblogic jDriver classes like weblogic.jdbc.rmi.SerialPreparedStatement,
weblogic.jdbc.rmi.SerialConnection etc and not from oracle thin driver.
Is this expected ? Why arent the corresponding classes from the Oracle Thin Driver
loaded ?Yes it is expected. The oracle classes are loaded, and used under the covers. All access
to JDBC connections and JDBC objects via our pools and DataSources will be via a
wrapper object of ours. This is necessary to allow us to retain control over the pool and
User Transactions. Also, because the DataSource is supposed to work whether from
a serverside class or an external client JVM, there will have to be an intermediary JDBC
object that acts as a proxy from the external client to the real thin driver connection
in the server. One can't ship JDBC connections across the wire as-is.
Thanks,
Praveen