Joda-Beans provides a small framework that adds properties to Java, greatly enhancing JavaBeans. An API is provided that defines a bean and property model, together with a code generator to make it work in practice.
The key concept is to allow each property on a bean to be accessed as an object. This enables technologies such as XPath, XML conversion, DB mappings, WebApp validation and Swing bindings.
Joda-Beans is licensed under the business-friendly Apache 2.0 licence.
Joda-Beans has been created to plug a gap in the Java language - properties. The concept of properties is familiar to those coding in almost every other modern language. Java stands alone in its pursuit of the terrible JavaBean approach, and personally I believe that properties should have been added to Java before generics and closures.
JavaBeans are typically created by manual coding or one-off IDE generation, such as by Eclipse. The same approach is taken to the creation of equals and hashCode methods. However, none of these approaches provides for a simple and fast mechanism to query a bean for the properties it exposes.
Joda-Beans provides a solution. As a developer, you just write the fields much as you would today. Then you add annotations to the bean and properties. Finally, you run a code generator, which creates the get/set methods plus framework methods that allow the properties to be effectively queried. A key point is that the code generator may be run again and again on the Java file, and is non-destructive.
See these sample classes used for testing - a simple user account class, example usage, example of validation.
Various documentation is available:
- The home page
- The helpful user guide
- The Javadoc
- The change notes for the releases
Release 1.7 is the current release. This release is considered stable and worthy of the 1.x tag.
Joda-Beans requires Java SE 6 or later and depends on Joda-Convert There are a number of optional dependencies which help with integration.
Available in the Maven Central repository
Please use GitHub issues and Pull Requests for support.