LanguageJJ
Doodle C64 Compressed image format
File type: Bitmap image file
Files with jj file extension could in the past be found as drawings made in Doodle program on Commodore 64.
Found 2 different file type records with the same jj filename suffix.
What is jj file?
File type category:
Bitmap image file
Date updated: June 23, 2025
The jj file extension was in the past used for a special compressed image format used on Doodle program for Commodore 64.
Doodle was a popular graphics editor on that platform.
How to open jj file?
You should be able to view these files using XnView.
How to convert jj file?
Use XnView to export *.jj files to other formats.
Suggested software to open jj file:
Associated software actions with the jj file
Programs for viewing jj files:
XnView MP (Multiplatform)
Software apps that print jj files:
XnView MP (Multiplatform)
JavaCC data
File type category:
Various data file
Date updated: September 7, 2017
The jj file extension is mainly associated with the JavaCC (Java Compiler Compiler) a parser generator for use with Java applications.
The jj file stores various data used for internal purposes of the Java Compiler Compiler.
How to open jj file?
It does not seem likely that you can manually open or otherwise access this type of .jj files.
How to convert jj file?
As far as we know, conversion for .jj file is not possible.
Suggested software to open jj file:
Associated software actions with the jj file
Software applications that handle other tasks involving jj files:
Java (Multiplatform)