Re: Tomcat - PostgreSQL - Cannot load JDBC driverclass"null" - Mailing list pgsql-jdbc

Thanks Dave,

Have extracted org.postgresql.Driver and put it under WEB-INF, creating
a structure of
Tomcat/webapps/ROOT/WEB-INF/lib/org/postgresql/Driver.class, made no
difference.

On suggestion 2, I don't appear to have a jre/lib/ext from root or
anywhere in the Tomcat structure, am I missing something here ??

Suggestion 3, would love to, but havent written any servlets before so
will need to get the book out.  Will let you know.


-----Original Message-----
From: Dave Cramer [mailto:Dave@micro-automation.net]
Sent: 26 September 2003 18:24
To: CRAIG GOLBY

Craig,

Ok, couple of things you can try. I seem to remember it not working in
common/lib, but then I've also given up on tomcat.

1) move the driver into the WEB-INF/lib dir
2) move the driver into the jre/lib/ext dir    this is real overkill
3) try writing a very small servlet that just loads the driver, remember
you have to set autoload or whatever in the web.xml file for this
servlet.

ie

class servletclass
{
    init(....)

    load postgres

}


Cheers,

Dave

On Fri, 2003-09-26 at 13:09, CRAIG GOLBY wrote:
> Sorry, bound to miss the obvious, it throws an Exception:-
>
> java.sql.SQLException: Cannot load JDBC driver class 'null'
>
> -----Original Message-----
> From: Dave Cramer [mailto:Dave@micro-automation.net]
> Sent: 26 September 2003 18:03
> To: CRAIG GOLBY
> Cc: pgsql-jdbc@postgresql.org
>
> Craig,
>
> So what happens, does it fail, does it run, does it throw an exeption?
>
> Dave
> On Fri, 2003-09-26 at 12:29, CRAIG GOLBY wrote:
> > Help, I am tearing my hair out.
> >
> > I am a newbie to Linux and Tomcat, and am therefore amazed that I
> > have
>
> > got as far as I have, that said I now seem to be stuck in front of a

> > brick wall, with no ladder !!
> >
> > Tomcat 4.1.24 is running on ServerOne (Red Hat 9), it is currently
> > serving out a couple of very basic JSP's and seems to be working
> > quite
>
> > well. ServerOne also has J2SDK 1.4.1_03 installed.  PostgreSQL 7.3
> > is running on ServerTwo (Red Hat 9).  Have also installed pgAdminIII

> > on both a Windows Laptop and ServerTwo.  The Laptop version works
> > fine, if a little unstable, so TCP/IP connectivity is working fine.
> >
> > Within PostgreSQL I have created a new Db called "PersonalDb",
> > within the public Schema I have created a table called "testOne".
> > TestOne has three columns, Id, FieldOne and DateStamp, and there are

> > currently
> > 2 rows of data within the table
> >
> > Sample of code used is below, along with a list of the Jar files in
> > common/lib.
> >
> > I have read through so many mailing lists now and tried so many
> > things
>
> > that I dont know what I have and havent done, am fairly sure that it

> > is either a configuration issue or a missing file so will no doubt
> > kick myself when I find out the answer.
> >
> > Any assistance would be greatly appreciated.
> >
> > Regards
> >
> >
> > Craig
> >
> >
> > *******************************************************
> > Server XML :- Tomcat/conf
> > *******************************************************
> > <Context path="/DBTest"
> >          docBase="DBTest"
> >          debug="5"
> >          reloadable="true"
> >          crossContext="true">
> >
> > <Logger className="org.apache.catalina.logger.FileLogger"
> >         prefix="localhost_DBTest_log." suffix=".txt"
> >         timestamp="true"/>
> >
> > <Resource name="jdbc/PersonalDb"
> >           type="javax.sql.DataSource"
> >           auth="Container"/>
> >
> > <ResourceParams name="jdbc/PersonalDb">  <parameter>
> >   <name>factory</name>
> >   <value>org.apache.commons.dbcp.BasicDataSourceFactory</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>driverClassName</name>
> >   <value>org.postgresql.Driver</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>url</name>
> >   <value>jdbc:postgresql://ServerTwo:5432/PersonalDb</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>username</name>
> >   <value>myUser</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>password</name>
> >   <value>myPassword</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>maxActive</name>
> >   <value>10</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>maxIdle</name>
> >   <value>30</value>
> >  </parameter>
> >
> >  <parameter>
> >   <name>maxWait</name>
> >   <value>10000</value>
> >  </parameter>
> >
> > </ResourceParams>
> > </Context>
> >
> > </Host>
> > </Engine>
> > </Service>
> >
> >
> > *******************************************************
> > Web XML  :-  Tomcat/webapps/root/WEB-INF
> > *******************************************************
> >   <description>PostgreSQL Test App</description>
> >     <resource-ref>
> >        <description>postgreSQL Datasource example</description>
> >        <res-ref-name>jdbc/PersonalDb</res-ref-name>
> >        <res-type>javax.sql.DataSource</res-type>
> >        <res-auth>Container</res-auth>
> >    </resource-ref>
> >
> >
> >
> > *******************************************************
> > My Class File
> > *******************************************************
> >
> >   public void init() {
> >     try{
> >       Context ctx = new InitialContext();
> >       if(ctx == null )
> >           throw new Exception("Boom - No Context");
> >       status = "checking CTX";
> >
> >       DataSource ds =
> > (DataSource)ctx.lookup("java:comp/env/jdbc/PersonalDb");
> >       status = "Completing Lookup of CTX";
> >
> >       if (ds != null)
> >         {
> >          status = "Creating Connection";
> >          Connection conn = ds.getConnection();   <----- FAILS HERE
> >          status = "Created Connection";
> >          if(conn != null)
> >            {
> >             foo = "Got Connection "+conn.toString();
> >             Statement stmt = conn.createStatement();
> >             ResultSet rst =
> >                 stmt.executeQuery(
> >                   "select Id, FieldOne, DateStamp from
> > Public.testOne");
> >             status = "Completing Select";
> >             if(rst.next())
> >             {
> >                foo=rst.getString(2);
> >                bar=rst.getInt(3);
> >             }
> >             status = "Looped through Resultset";
> >             conn.close();
> >            }
> >         }
> >       else {status = "Fell into Else";}
> >     }catch(Exception e) {
> >       e.printStackTrace();
> >         status = status + ", now in exception block :-" +
> > e.toString();
> >
> >     }
> >  }
> >
> > *******************************************************
> > Class Files in Tomcat/common/lib
> > *******************************************************
> > activation.jar
> > ant.jar
> > collections-2.1.jar
> > commons-collections.jar
> > commons-dbcp-1.0.jar
> > commons-dbcp.jar
> > commons-logging-api.jar
> > commons-pool.jar
> > jasper-compiler.jar
> > jasper-runtime.jar
> > jdbc2_0-stdext.jar
> > jndi.jar
> > jta.jar
> > mail.jar
> > naming-common.jar
> > naming-factory.jar
> > naming-resources.jar
> > pg73jdbc3.jar
> > pool-1.0.1.jar
> > postgresql.jar    (Copy of  pg73jdbc3.jar)
> > servlet.jar
> >
> >
> >
> >
> >
> --
> Dave Cramer <Dave@micro-automation.net>
>
>
>
--
Dave Cramer <Dave@micro-automation.net>