BLUEJ, BlueJ Package File (.bluej)
The BLUEJ Developer file format
BlueJ is an integrated developing environment (IDE) that uses the Java programming language. Package files created in the program are saved in the BLUEJ format. The program is mainly used for education and teaching. It can also be used for software development on a smaller scale though.
Technical details of BLUEJ files
The BLUEJ package file contains information about the creation date of the program created in BlueJ. The file is created in the project folder of the BlueJ project and is typically named package.bluej when it is saved. This file is created automatically when a new BlueJ project is created. Clicking on the BLUEJ file will open the BlueJ program.