Cayenne.apache.org Website Review

Apache Cayenne™ is an open source Ja*a object-to-relational mapping framework Cayenne is distributed with CayenneModeler - a complete GUI mapping tool that supports reverse-engineering of RDBMS schemas, editing object-relational mapping projects, generation of Ja*a source code for the persistent objects and other functions. Cayenne allows you to design your data model in a single place - the database. Other layers (OR mapping and Ja*a objects) are synchronized automatically via CayenneModeler or a build script, so you don't have to repeat yourself. Such approach is called database-first. It saves you development time and prevents errors by ensuring that your model is in sync across multiple layers. It is also quite flexible. It works well with common DB migrations frameworks like Liquibase or Flyway, allows object structure customizations and is designed for iterative Most ORM frameworks require you to manage transactions manually or with external tools like Spring. Also you must always ensure you stay within transaction bounds when traversing relationships between objects. Cayenne takes a notably different approach, freeing you from writing lots of trivial code. Transaction management happens automatically behind the scenes. Object graph can be expanded lazily At the same time Cayenne works well with external transaction managers. It also has its own transaction API that can be used to run At the heart of Cayenne persistence API lies ObjectContext. ObjectContext can be thought of as a unit of work. It has its own copy of persistent objects. While vaguely similar to JPA EntityManager, ObjectContext is closer to a version control client. It is not connected to the database except when a read or write operation is in progress, it doesn't hold on to any resources (such as DB without affecting the DB). There is even a version of ObjectContext that can run in an entirely different JVM from the main app, and Cayenne stack is built around a small dependency injection (DI) container responsible for configuring and binding all framework