Apache Cayenne is an open source persistence framework licensed under the Apache License, providing object-relational mapping (ORM) and remoting services. With a wealth of unique and powerful features, Cayenne can address a wide range of persistence needs. Cayenne seamlessly binds one or more database schemas directly to Java objects, managing atomic commit and rollbacks, SQL generation, joins, sequences, and more. With Cayenne's Remote Object Persistence, those Java objects can even be persisted out to clients via Web Services. Or, with native XML serialization, objects can be even further persisted to non-Java clients - such as an Ajax-capable browser.
Cayenne is designed to be easy to use, without sacrificing flexibility or design. To that end, Cayenne supports database reverse engineering and generation, as well as a Velocity-based class generation engine. All of these functions can be controlled directly through the CayenneModeler, a fully functional GUI tool. No cryptic XML or annotation based configuration is required! An entire database schema can be mapped directly to Java objects within minutes, all from the comfort of the GUI-based CayenneModeler.
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