SQuirreL SQL Client
SQuirreL SQL Client is a graphical Java program that will allow you to view the structure of a JDBC compliant database, browse the data in tables, issue SQL commands etc. The minimum version of Java supported is 1.3
https://sourceforge.net/projects/squirrel-sql/
https://www.squirrelsql.org/
Pixelitor
Pixelitor is a free and open source image editing software that supports layers, layer masks, text layers, filters, multiple undo etc.
https://sourceforge.net/projects/pixelitor/
Jalmus
Jalmus is a free, open source music education software helping the musicians, especially pianists, to improve their sight-reading. You can train to read music with both exercises on notes or rhythms.
https://sourceforge.net/projects/jalmus/
https://jalmus.net/
DataMelt
interactive environment for scientific computation, data analysis and data visualization
https://sourceforge.net/projects/dmelt/
https://jwork.org/dmelt/
QRCodeGen
QRCodeGen is a free application which generates QR Codes from WLAN credentials,VCards, e-mail addresses, URLs, free text, geographic coordinates etc.The QR Code can be printed, saved as BMP, GIF or PNG, or copied to clipboard to use in other applications.

https://sites.google.com/site/qrcodeforwn/
https://sites.google.com/site/qrcodeforwn/home/qr-code-generator-for-wireless-networks
Java Mass Jpeg Resizer Tool
Java Mass JPEG, create your photo album in a few minutes, resize and pack, create galleries.
https://sourceforge.net/projects/jmjrst/
Art of illusion
Art of Illusion is a full featured 3D modelling, rendering, and animation studio. It is written entirely in Java, and can run on almost any operating system.
https://sourceforge.net/projects/aoi/
https://www.artofillusion.org/
Angry IP scanner
Angry IP scanner is fast and friendly network scanner for Windows, Linux, and Mac. It is very extensible, allowing it to be used for very wide range of purposes, with the primary goal of being useful to network administrators.
https://sourceforge.net/projects/ipscan/
https://angryip.org/
freeplane
Application for Mind Mapping, Knowledge Management, Project Management. Develop, organize and communicate your ideas and knowledge in the most effective way.
https://sourceforge.net/projects/freeplane/
https://www.freeplane.org
GanttProject
Free project scheduling and management tool
https://sourceforge.net/projects/ganttproject/
https://www.ganttproject.biz/
Jubler Subtitle Editor
Jubler is a tool for editing text-based subtitles. It can be used an an authoring software for new subtitles or as a tool to convert, transform, correct, and refine existing subtitles.
https://github.com/teras/Jubler/
ArgoUML
UML modeling tool
https://sourceforge.net/projects/argouml/
https://argouml-tigris-org.github.io/
ImageJ
Image Manipulation
https://sourceforge.net/projects/imagej/
https://imagej.nih.gov/ij/
jpdftweak (Beta)
jPDF Tweak is a Java Swing application that can combine, split, rotate, reorder, watermark, encrypt, sign, and otherwise tweak PDF files.It can be used to make printable booklets from your PDFs, to add PDF bookmarks, effects (page transitions), to combine multiple PDF files, to watermark them, to rotate pages that do not fit, to attach files to your PDF, to encrypt and sign your PDFs, to change metadata (like author or keywords), and much more.

https://sourceforge.net/projects/jpdftweak/
atunes
Cross-platform player and audio manager
https://sourceforge.net/projects/atunes/
https://www.atunes.org/
Jdiskreport
JDiskReport enables you to understand how much space the files and directories consume on your disk drives, and it helps you find obsolete files and folders.The tool analyses your disk drives and collects several statistics which you can view as overview charts and details tables.

https://www.jgoodies.com/freeware/jdiskreport/
mucommander
muCommander is a cross-platform file manager with a dual-pane interface that features support for many filesystems and archives formats, bookmarks, credentials management, themes, multiple windows, full keyboard control, and many configuration options.
https://sourceforge.net/projects/mucommander/
https://www.mucommander.com/
jEdit
jEdit is a programmer's text editor written in Java. It uses the Swing toolkit for the GUI and can be configured as a rather powerful IDE through the use of its plugin architecture.
https://sourceforge.net/projects/jedit/
https://www.jedit.org/
Sweet Home 3D
Sweet Home 3D is an interior design application that helps you to quickly draw the floor plan of your house, arrange furniture on it, and visit the results in 3D.
https://sourceforge.net/projects/sweethome3d/
https://www.sweethome3d.com/
JPC X86 PC emulator
x86 PC emulator
https://sourceforge.net/projects/jpc/
ytd2
Java Youtube downloader
https://sourceforge.net/projects/ytd2/
Tiny Java Webserver
TJWS is an Open Source HTTP Server and Servlet container written in 100% Java. It's designed to be light weight, high performance, secure, embeddable, extensible and flexible. Very small footprinted (~99K), CGI, J2EE/JSP compatible. Servlet spec 3.0
https://sourceforge.net/projects/tjws/
Hodoku - Sudoku
Sudoku generator/solver/analyzer written in Java (English and German). Lots of human style techniques (singles, subsets, LCs, fish, wings, uniqueness, coloring, chains, ALS), powerful analyzer (manage multiple solutions for one sudoku). Includes Learning and training modes and a booklet printer.
https://sourceforge.net/projects/hodoku/
impro-visor
Impro-Visor is a music notation tool for producing monophonic lead sheets. Chord symbols are used to generate backing tracks automatically.
https://github.com/Impro-Visor/Impro-Visor
https://sourceforge.net/projects/impro-visor/
FidoCADJ
A multiplatform vector drawing program with a complete library of electronic symbols. Schematics and drawings are stored in a very compact text format. There is no netlist concept behind the drawings (so no simulation, and this is a choice) but this allows a great graphical flexibility and ease of use, making FidoCadJ the perfect tool for exchange sketches in forum and newsgroup discussions with a few clicks.
http://darwinne.github.io/FidoCadJ/
https://sourceforge.net/projects/fidocadj/