Simplicity for Java
Java GUI development environment for any Java-enabled platform. Professional version includes database integration, servlet development, and cross-platform testing. [Commercial] http://www.datarepresentations.com/
SpeedJG
A GUI builder tool to create state-of-the-art Java Swing applications. The meta data that describe the GUI are mapped to XML from where Components can be created on the fly or Java source code is generated. [Commercial] http://www.wsoftware.de/SpeedJG/
ThinCLet
An add-on for Thinlet, the lightweight GUI toolkit for Java. ThinCLet assist to componentize Thinlet applications. It is written by Koen Roevens. [Open source, LGPL] http://thinclet.sourceforge.net/
jvider
A GUI builder tool for Java Swing applications. [Shareware] http://jvider.com/
JFrameBuilder
Enables Java developers to create GUI applications using drag-and-drop interface. [Commercial] http://www.mars3000.com
Adaptable Layout Environment (ALE)
Allows laying out components in a program via a configuration file rather than hard-coding using a layout manager. http://locutus.kingwoodcable.com/jfd/java/ale/ale.html
GridBagger
A visual editor for creating GUI's with Java's GridBagLayout class. [Freeware] http://www.cellspark.com/GridBagger.html
JAXFront
A XML schema based GUI rendering engine generates presentation GUIs "on-the-fly", using an XML schema based representation of the business model. It offers a powerful Visual Editor (XUI-Editor) for adjusting or completely redesign GUI and Forms with drag and drop. http://www.jaxfront.org/
Abeille Forms Designer
A GUI builder for Java applications. Developers and designers can create complex, professional forms. Designers can drop and drop components onto a WYSIWYG editor. [Open source, LGPL] https://abeille.dev.java.net/
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