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Amen! http://www.javaworld.com/javaworld/jw-02-2002/jw-0201-jca2.html
The sample class files
Next, let's delve into the Java classes required to implement the sample JCA
adapter. The adapter includes two class categories:
Managed classes: The application server calls managed classes to perform the
connection management. They're needed only if the application server is
managing the connection (via a connection pool), a likely situation.
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