Michael Bayne
70 lines
3.1 KiB
Markdown
70 lines
3.1 KiB
Markdown
# Depot Persistence Library
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Depot is a relational persistence library for Java. It is an ORM library, but has aims that are
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somewhat different from the popular "managed" persistence libraries like Hibernate and others.
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## Design Goals
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* Eliminate (as much as possible) the use of raw SQL, instead providing Java classes that allow
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the expressions of queries and updates in as concise but compile-time checkable a manner as
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possible.
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* Reduce the pain of schema and data migrations as much as possible, but not so much that the
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system used to do the migrations is too complex for anyone to understand or use properly.
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* Use annotations to layer database metadata over the top of (almost) POJOs.
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* Use annotations that are syntactically and semantically equivalent to EJB3 persistence
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annotations wherever possible.
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* Support multiple database backends (currently MySQL, Postgresql and HSQLDB).
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* Provide caching support (currently integrated with EHCache).
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* Keep an eye toward eventual support for sharded databases (not yet implemented).
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Depot studiously avoids ever doing anything magical. You only access the database when you make a
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method call requesting that records be read from the database or records be updated in the database.
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Depot attempts only to be a concise, compile-time checkable veneer over raw database access that
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conveniently models database tables as Java objects.
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In this way Depot is more of an evolution of DAO-like libraries of the past than a pared down
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sibling of the managed persistence libraries of the present. It distinguishes itself by taking
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advantage of annotations to concisely express database metadata and by striving to stay out of your
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way as much and surprise you as little as possible.
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## Code Examples
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Here's are some example to give you a taste of what code using Depot looks like.
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* A [simple code example](docs/SimpleCodeExample.md)
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* Various [example queries](docs/ExampleQueries.md)
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[API docs](http://threerings.github.io/depot/apidocs/) are also available.
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## Features
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Depot supports a number of very useful features. Here are a few of the main features for which time
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has permitted documentation:
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* [Schema and Data migration](docs/SchemaMigration.md)
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* [Caching](docs/Caching.md)
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## Getting Started
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If you want to use Depot on your project, check the following page for information on getting Depot
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and dependencies via Maven or manually, as well as what sort of configuration Depot requires to
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start talking to your database.
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* [Configuring and integrating](docs/Configuration.md) Depot with your project
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## Discussion
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Feel free to pop over to the [OOO Libs](http://groups.google.com/group/ooo-libs) Google Group to
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ask questions and get (and give) answers.
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## History
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Depot was started in September of 2006 by [Three Rings](http://www.threerings.net/) as a part of
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their [Whirled](http://www.whirled.com/) project. Its primary authors are Michael Bayne and Pär
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Winzell.
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## License and Distribution
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Depot is released under the New BSD License. The most recent version of the library is available at
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https://github.com/threerings/depot/
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