JNDI Driver not found with Derby database connection

[John Storta Jr.]

I have a web app which uses a Derby database. The connection to the database establishes fine while using DriverManager.getConnection(), but if I try to establish the connection using JNDI, I get an error that the driver cannot be found.

context.xml

    <Resource name="jdbc/testdb" auth="Container"
              type="javax.sql.DataSource"
              driverClassName="org.apache.derby.jdbc.ClientDriver" url="jdbc:derby://localhost/testdb"
              maxActive="10" maxIdle="4"/>

web.xml

    <resource-ref>
        <res-ref-name>jdbc/testdb</res-ref-name>
        <res-type>javax.sql.DataSource</res-type>
        <res-auth>Container</res-auth>
        <res-sharing-scope>Shareable</res-sharing-scope>
    </resource-ref>

Database Access Code

    public static final String DRIVER = "org.apache.derby.jdbc.ClientDriver";
    public static final String DBURL = "jdbc:derby://localhost:1527/testdb";

    public static Connection createConnection() {
        Connection dbConnection = null;
        boolean dbOpen = false;
        Context initCtx;
        Context envCtx;
        DataSource ds;

        try {
            //The connection establishes fine and everything works as expected if I use this code
            System.out.print("Connecting to " + DBURL + "...");
            Class.forName(DRIVER).newInstance();
            dbConnection = DriverManager.getConnection(DBURL);

            //If I use this code instead, then I get the error listed below
            //initCtx = new InitialContext();
            //envCtx = (Context) initCtx.lookup("java:comp/env");
            //ds = (DataSource) envCtx.lookup("jdbc/testdb");
            //dbConnection = ds.getConnection();

...

Error Message
org.apache.tomcat.dbcp.dbcp.SQLNestedException: Cannot load JDBC driver class 'org.apache.derby.jdbc.ClientDriver'


The obvious expected cause is that the DerbyClient.jar file is not in the classpath. But that is not the case here. The jar file is exactly where it should be and this can be verified by switching to the DriverManager method.

What am I missing?

Thanks

[David O'Meara]

When you use the DriverManager, the web application loads the Driver and creates the Connection so therefore the Driver jar should be placed in the <CONTEXT>/WEB-INF/lib directory.
When you use JNDI, the connection gets managed and created by the container, so the Driver jar needs to be visible to the container in the container lib directory (not sure what you're using)

[John Storta Jr.]

Ahhhhhhh. It makes perfect sense now. Definitely one of those that seems obvious after the fact.

Thank you for getting me back on track.

John S.

[David O'Meara]

No charge!