Problem with JDBC driver for Oracle 10g

Question

Hi.
I've successfully accessed a MySQL database via a DataSource from a servlet (that uses a DAO). However, when I try to do the same with an Oracle 10g Database, I get the error message:
Cannot load JDBC driver class 'oracle.jdbc.driver.OracleDriver'
I'm using J2SE1.5.0/5.0 and ojdbc14.jar, the latter of which I downloaded this afternoon as the latest driver JAR available on the Oracle site. As with the MySQL driver, I've placed it in the commons\lib folder within Tomcat. (I've also, of course, made the necessary modifications to server.xml and web.xml.)
Upon examining the ReadMe file at the top of the Oracle download page, I found that the oracle.jdbc.driver package is now deprecated and all references to oracle.jdbc.driver should be replaced with oracle.jdbc. However, I got a similar error message when I tried this modification. Upon examining the contents of ojdbc.jar, I found that the driver was there and that it was, in fact, still oracle\jdbc\driver\OracleDriver!
It appears as though the Oracle site has not been updated with a driver that matches its latest documentation. However, this does not explain why the driver is not even being loacted when it is in the correct place. Can anybody shed any light on this? Any help would be much appreciated.
Thanks in anticipation.
Cheers.
Jan

Answer 1

I've successfully accessed a MySQL database via a
DataSource from a servlet (that uses a DAO). However,
when I try to do the same with an Oracle 10g
Database, I get the error message:
Cannot load JDBC driver class 'oracle.jdbc.driver.OracleDriver'
That's different from a ClassNotFoundException.
>
I'm using J2SE1.5.0/5.0 and ojdbc14.jar, the latter
of which I downloaded this afternoon as the latest
driver JAR available on the Oracle site. So you got ojdbc14.jar or ojdbc14_g.jar under the 10g drivers?
As with the
MySQL driver, I've placed it in the commons\lib
folder within Tomcat. I think it's a better idea to put in the WEB-INF/lib directory of your Web app rather than commons/lib. WAR files are a very good idea, too.
(I've also, of course, made the
necessary modifications to server.xml and web.xml.)So you're using a JNDI data source? It sounds to me like that's where the problem is.
You should not have to edit the server.xml at all. If you put the <ResourceParams> in a context XML file with the same name as your WAR file into the TOMCAT_HOME/webapps directory it'll be picked up automatically. (It might also be accessible in the META-INF directory for your app, but I haven't done it that way.)
Upon examining the ReadMe file at the top of the
Oracle download page, I found that the
oracle.jdbc.driver package is now deprecated and all
references to oracle.jdbc.driver should be replaced
with oracle.jdbc.
However, I got a similar error
message when I tried this modification. Upon
examining the contents of ojdbc.jar, I found that the
driver was there and that it was, in fact, still
oracle\jdbc\driver\OracleDriver! The fully-resolved class name you should be using MUST match the class that's in the ojdbc14.jar that you're using. Look in the JAR for the definitive answer: the one that I downloaded is still using the oracle.jdbc.driver package for OracleDriver.class. Ignore the docs - use the name that's in the JAR.
It appears as though the Oracle site has not been
updated with a driver that matches its latest
documentation. That often happens with docs.
However, this does not explain why the
driver is not even being loacted when it is in the
correct place. Can anybody shed any light on this?
Any help would be much appreciated.I think the problem lies in your web.xml and server.xml
I'd recommend that you decouple the JDBC from the Web app for now. See if you can connect to Oracle using a simple desktop app and leave the Web piece out of the equation for now. Once you can do that, you'll be certain that the parameters you're using are correct and you can turn your attention to getting the Tomcat configuration right.
PS - I'm using Oracle 9.2.0.1 and Tomcat successfully right now, so it can be done.