Using JDBC 2.0 Data Sources

Using JDBC 2.0 data sources to access a database provides performance advantages, such as transparent connection pooling, enhanced productivity by simplifying code and implementation, and code portability.

If there is a datasource by the name ”xyz’ on Application Server 6.x application and you do not want any impact on your JNDI lookup code, make sure that the datasource you create for Application Server 8.1 is prefixed with jdbc. For example: jdbc/xyz.

For information on configuring JDBC Datasources, see Chapter 3, JDBC Resources, in Sun Java System Application Server Enterprise Edition 8.1 2005Q2 Administration Guide.

Looking Up the Data Source Via JNDI To Obtain a Connection

To obtain a connection from a data source, do the following:

To Connect to a Data Source

1. Obtain the initial JNDI context.

   To guarantee portability between different environments, the code used to retrieve an InitialContext object (in a servlet, in a JSP page, or an EJB) is as follows:

   InitialContext ctx = new InitialContext();

2. Use a JNDI lookup to obtain a data source reference.

   To obtain a reference to a data source bound to the JNDI context, look up the data source’s JNDI name from the initial context object. The object retrieved in this way is cast as a DataSource type object:

   ds = (DataSource)ctx.lookup(JndiDataSourceName);

3. Use the data source reference to obtain the connection.

   This operation requires the following line of code:

   conn = ds.getConnection();

   Application Server 6.x and Application Server both follow these technique to obtain a connection from the data source.