* Exception hierarchy enabling sophisticated error handling independent
* of the data access approach in use. For example, when DAOs and data
* access frameworks use the exceptions in this package (and custom
* subclasses), calling code can detect and handle common problems such
* as deadlocks without being tied to a particular data access strategy,
* such as JDBC.
* <p>All these exceptions are unchecked, meaning that calling code can
* leave them uncaught and treat all data access exceptions as fatal.
* <p>The classes in this package are discussed in Chapter 9 of
* <a href="http://www.amazon.com/exec/obidos/tg/detail/-/0764543857/">Expert One-On-One J2EE Design and Development</a>
* by Rod Johnson (Wrox, 2002).