Client connector to a JDBC database. To send a request to the server,
create a new instance of a client supporting the JDBC Protocol and invoke the
handle() method. Alternatively, you can create a new Call with the JDBC
URI as the resource reference and use an XML request as the entity.
Database connections are optionally pooled using Apache Commons DBCP.
Context allowing access to the component's connectors, reusing the Servlet's
logging mechanism and adding the Servlet's initialization parameters to the
context's parameters.