The Netty project is an effort to provide an asynchronous, event-driven network application framework and tools for rapid development of maintainable, high-performance, high-scalability protocol servers and clients. In other words, Netty is a NIO client server framework that enables quick and easy development of network applications such as protocol servers and clients. It simplifies and streamlines network programming such as TCP and UDP socket servers.
OpenEJB is a simple, lightweight Enterprise JavaBeans (EJB) container and server. You can embed OpenEJB in your own applications, or in a Web application server like Tomcat, or run it as a standalone EJB server. It supports EJB 3.0, 2.1, 2.0, and 1.1, and has partial support for EJB 3.1.
Barcode4J is a barcode generation package. The following symbologies are currently implemented: Interleaved 2 of 5, Code 39, Codabar, Code 128, UPC-A and UPC-E (with supplementals), EAN-13 and EAN-8 (with supplementals), EAN-128, POSTNET, Royal Mail Customer Barcode, PDF417, and DataMatrix. Supported output formats are SVG, EPS (Encapsulated PostScript), Bitmap images (such as PNG or JPEG), and Java2D (AWT). Additional features include two APIs (XML-oriented and Bean-style), a Servlet with support for SVG, EPS, and bitmap output, a command-line interface, a demonstration applet, and extensions for Apache Xalan-J, SAXON, and Apache FOP.
Echomine Feridian is an easy-to-use Java API that gives you quick and easy access to the XMPP network used in IM services such as Google Talk. The API allows you to communicate with Jabber/XMPP servers for sending and receiving instant messages, presence management, and custom extensions to the XMPP protocol.
VRaptor 2 is a Web-based MVC and IOC framework based on many frameworks and ideas (Seam, Stripes, Webwork, Hibernate Annotations, etc). It makes full use of Java 5 Annotations. It favors convention over configuration, because configuration in XML/properties/annotations is always easy to make mistakes and repetitive (aka copy and paste in many places). This framework uses a more imperative approach, instead of having many XML files to configure lifecycle and other properties. Most of the settings go inside plain Java objects (POJO), so the team knows exactly what is going on and where.