web server - Borland Technical Publications

Other Considerations
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Adapter can be deployed to an application server without incident, it cannot be
deployed to JNDI outside the aegis of an application server, as a non-managed
Connector. Also, including a javax.naming.spi.ObjectFactory implementation source
Adapter with backup mechanism for JNDI Reference-based connection factory
lookup.
The Resource Adapter which specifies an connection factory or connection interface
while not implementing that interface in its connection factory or connection class,
respectively. Section 10.6 “Resource Adapter XML DTD” in the Connectors spec
discusses the related requirements. To illustrate, let's say that in the ra.xml of a
particular Resource Adapter, you have the following elements:
//...
java.sql.Connection
com.shme.shmeAdapter.ShmeConnection
//...
But your implementation of ShmeConnection is as follows:
package shme;
public class ShmeConnection
{
private ShmeManagedConnection mc;
public ShmeConnection( ShmeManagedConnection mc )
{
System.out.println( "In ShmeConnection" );
this.mc = mc;
}
}
Any attempt to invoke getConnection() on this Resource Adapter's connection
factory will result in a java.lang.ClassCastException, as you're indicating to the
appserver in ra.xml that connection objects returned by the Resource Adapter are to
be cast to java.sql.Connection.
Working with a Poor Resource Adapter Implementation
To work around a poor Resource Adapter implementation, perform the following:
Extend the connection factory and/or connection class of the Connector, and have the
extension correctly implement the poorly implemented code. For example, when
dealing with a connection factory which implements Serializable, and doesn't
implement Referenceable the idea is to extend the original connection factory to
implement Referenceable, which means implementing getReference() and
setReference().
Chapter 27: Using VisiConnect 279