JMermaid is the older version of the modelling tool. It has been superseded by the combination of MERLIN and the Code Generator.

If you really need the standalone Java tool, you can download the 2020 version of JMermaid here. However, the tool will may not be able to load models created with MERLIN, and it is no longer maintained.

An installation of java is required to run the tool.

The use of the tool is free. As you'll see the installation comes with a license that you need to accept. If asked for a student number, just use a random number.

For use in a professional setting, however, the KU Leuven requests a license that is signed on paper. Please contact Monique Snoeck if you would like to use the tool in a professional setting.

After installing java and downloading JMermaid, the tool can be executed as follows:

For windows users:
1.Unzip the file to a suitable location (e.g. c:\Program Files\JMermaid2016)
2. Run JMermaid by double clicking the JMermaid20161201.jar file (in the unzipped location)

For MAC OS X users: unfortunately there is no stable version of JMermaid supported on MAC OS. JMermaid seems to run fine with a JRE 1.6, but not with more recent JREs. You can try the following steps:
1. Download the JMermaid for MAC installation file
2. Unzip the file to a suitable location (e.g. the Downloads folder)
3. Open a terminal (Applications - Utilities - Terminal)
4. In the terminal browse to the directory containing JMermaid (e.g. by typing: cd Downloads/JMermaid;)
5. Enter the command: ./1.6.0.jdk/Contents/Home/bin/java -jar JMermaid.jar to force execution under JRE 1.6. The path ./1.6.0.jdk/ refers to the map where the jdk 1.6 is located) Don't forget the dot in the beginning!