.DEFS File Extension

BlueJ Settings File

Developer University of Kent
3.6  |  5 Votes

What is a DEFS file?

Configuration file created for BlueJ, a Java development environment; contains administrator settings for the BlueJ program such as the desired language and location of libraries.

More Information

There are two ways to change BlueJ configuration settings:

  1. To change user options, with the application open, select BlueJ from the menu bar, then Preferences.... You can alter settings in this dialog box.
  2. To change administrator options, open the file located at: BLUEJ_HOME/​lib/​bluej.defs. If on a Mac, right-click the BlueJ application, select Show Package Contents, then Contents, then Resources, then Java. You should then see the bluej.defs file and other DEFS files.

Once you open a DEFS file, it will contain a list of properties in the following format: property-name = value

The property name should never be changed but the values can be changed to alter the configuration.

Common DEFS Filenames

bluej.defs - The default settings file located in the BlueJ program.

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Programs that open or reference DEFS files


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