Apache Ant is a Java-based build tool. In theory, it is kind of like Make, but without Make’s wrinkles.

Continuum is a continous integration server for building Java based projects.

Antmod’s repository management, release descriptors, working with modules

CruiseControl is a framework for a continuous build process. It includes, but is not limited to, plugins for email notification, Ant, and various source control tools. A web interface is provided to view the details of the current and previous builds.
CruiseControl is distributed under a BSD-style license and is free for use. CruiseControl adheres to an open source model and therefore makes the source code freely available.
CruiseControl is maintained and developed by a group of dedicated volunteers.
URL:http://cruisecontrol.sourceforge.net/
Licence: BSD License

CPMake is a make utility written in Java to make anything (C, C++, Java, C#, XSL …)

Invicta is an open-source build management tool. Using simple project definition files, it generates powerful build scripts (Apache ANT’s), while hiding their complexity. Furthermore, Invicta is a modular framework that allows advanced developers add their own customized types of components, which means writing once ANT code that can later be used by all the developers in their project or company simply by specifying the new type name.
URL: http://invicta.sourceforge.net/
Licence: LGPL

GenJar is a specialized Ant task that builds jar files based on class dependencies rather than simply the contents of a directory.
GenJar was originally created by John W. Kohler (jake at riggshill.com).
Work is underway on GenJar2. GenJar2 will be a functional replacement of GenJar, but build file syntax will change. Some of the features of GenJar2 include:

Syntax consistent with Ant’s jar task
Replacement of GenJar’s with Ant’s
Replacement of GenJar’s with with Ant’s
BCEL for class dependency checking

The original GenJar branch will be maintained for as long as there is …