Apache Ant - Ant is a Java-based build tool, a great make-like tool for Java projects. Ant integrates well with other XP tools like JUnit. According to Ant's original author, James Duncan Davidson, the name is an acronym for "Another Neat Tool".
Axis - Apache Axis is an implementation of the SOAP ("Simple Object Access Protocol") submission to W3C. Axis 1.1 has proven itself to be a reliable and stable base on which to implement Java Web services. There is a very active user community and there are many companies who use Axis for Web services support in their products.
DOM4J API - Dom4j is an easy to use, open source library for working with XML, XPath and XSLT on the Java platform using the Java Collections Framework and with full support for DOM, SAX and JAXP.
Eclipse - Eclipse is an open source community whose projects are focused on providing an extensible development platform and application frameworks for building software. The Eclipse integrated development environemtn (IDE) is one of the leading free and open source development environments for java.