Drools is a Rete-based rules engine written in Java, but able to run on Java and .Net. it is designed to allow pluggeable language implementations. Currently, rules can be written in Java, Python, and Groovy. It also enables domain-specific languages (DSLs) via XML using a schema defined for your problem domain. DSLs consist of XML elements and attributes that represent the problem domain. An XML authoring tool provides a semi-rapid development environment with a drag and drop type interface based on the provided schema.
Salsa is a collection of Swing add-ons. It includes new widgets such as auto-complete textboxes or tree tables, new data models such as XML tree models, UI tree models, or Java Bean table models, new common dialogs such as a font chooser, new convenience methods such as center frame on screen, and much more.
Cypress is an open-source Cascading Style Sheet (CSS) parser that lets you add well-documented, standardized name/value pairs (a.k.a. CSS style properties) to your own XML markup languages. It supports inline styles so you can add style properties to individual XML tags using the style attribute or external style sheets so that you can store style rules for reuse in separate, XML-free text documents. Cypress supports three forms of selectors to match your XML tags and style rules, that is, element selectors, class selectors, and id selectors.
Caramel is a collection of open-source Java utility classes and includes class utility methods, color utility methods and constants that let you use more than a hundred predefined colors by name (such as azure, chocolate, deepskyblue, indigo, etc.), data utility methods to get a timestamp in a RFC-1123 format, file utility methods to get file extensions or to save a stream to a file, MIME utility methods, net utility methods, string utility methods to fill in templates, and much more.
Rome is a set of Atom/RSS Java utilities that make it easy to work in Java with most syndication formats. It accepts all current flavors of RSS (0.90, 0.91, 0.92, 0.93, 0.94, 1.0, and 2.0) and Atom 0.3 feeds. Rome includes a set of parsers and generators for the various flavors of feeds, as well as converters to convert from one format to another. The parsers can give you back Java objects that are either specific for the format you want to work with, or a generic normalized SyndFeed object that lets you work on with the data without bothering about the underlying format.