Apache Cayenne

Apache Cayenne is what in the industry professionals call a "persistence framework," a tool for automating the interaction and storage of data in relational databases.

How Cayenne works is to bind database schemas to Java objects, persisting object changes to the database and vice versa.

This enriches one with the other's features, providing more in-depth control over the database's data thanks to Java's powerful object manipulation features.

Along with Cayenne's source, an desktop GUI called the "CayenneModeler" is also included, small application for managing databases and their schemas using a visual interface.

Features:

• Velocity-based class generation engine
• A complete object query syntax
• Relationship pre-fetching
• On-demand object faulting
• On-demand relationship faulting
• Object inheritance
• Data caching
• Database auto-detection
• Generic persisted objects
• Scalable on a per-project basis
• Documentation

What is new in this release:

• MySQL JDBC Batching
• Method "readNestedProperty" Should Resolve Through Iterative Invocations onto DataObject and Not Complete Within Cayenne.readNestedProperty
• java.io.NotSerializableException when using OSCache for query cache with prefetches and persitent cache.
• NPE when persisting a newly instatiated object
• Investigate auto-increment columns on DB2 and switch the adapter policy to support them
• Flattened attribute queries are incorrectly generated
• Memory information for about dialog
• OutOfMemory when selecting "Remove Foreign Keys Mapped as Object Attributes"
• NPE using DataContext.objectFromDataRow for a nested context
• Maven cgen: all and datamap modes can not be activated
• Problem in derby: comparison operators are not supported on Clob object values.
• POST_LOAD is not called on prefetched objects
• Callbacks: POST_UPDATE is called on updated removed object, instead of POST_REMOVE
• Reserved words mapping in WHERE clause
• cgen: duplicate callback methods
• Vertical inheritance is broken for subclasses with more than one flattened attribute
• Modeler trivial bug NullPointerException on remove
• BaseQueryMetadata.setPrefetches() causes a shared lock
• Unicode character types on MS SQL 2008 server aren't recognized.

What is new in version 3.0:

• Cache group removed from modeler query.
• Error resolving fault, no matching row exists in the database.
• Pkgenerator is accessed needlessly for join tables with own database generated PK.
• Modeler: error dialog doesn't show the correct version.
• Exception when attempting to "Infer Relationships".

What is new in version 3.0 RC1:

• Changes/New Features:
• Undo/Redo support in modeler
• Bug Fixes:
• Enum construction requires string name of enum
• Query SQL syntax with join and OR on Oracle8 (and maybe OpenBase)
• EJBQL doesn't support null parameters
• Error committing CLOB on Oracle8
• Many validation errors when we remove dbEntity
• Stop bundling cayenne-agent.jar with the distro
• Embeddable validation error in CM on custom Java types
• Entering a custom Java Type in CM for an ObjEntity blanks out DB fields
• Modeler is trying to load data object classes when selecting a query
• Modeler cannot unset inheritance
• EJBQL: joins on joined table not added to generated SQL
• Exclude asm jars from compile maven dependencies
• CreateIfNoSchemaStrategy runs too late - pk generation happens before
• Fail to create new listener for the DataMap

Limitations:

• CayenneModeler