Home : File Types : J File

.J File Extension

3 file types use the .j file extension.

File Type 1Java Source File

3.3 (24 Votes)
CategoryDeveloper Files


This file is saved in a plain text format. You can open and view the contents of this file using a text editor.

What is a J file?

Contains program source code written in the Java programming language; may include the source code for a complete program or may be one of many files referenced by a Java programming project.

More Information

Java source files most often have a .JAVA extension.

Open and view .J files with File Viewer Plus.
Programs that open J files
Updated 8/17/2010

File Type 2JAR Archive

2.8 (5 Votes)
CategoryCompressed Files


File format categories include Binary, Text, XML, and Zip. The format of this file type has not been determined.

.J File Association 2

Compressed file archive created with JAR, the successor to the ARJ file compression program (which created .ARJ files); JAR is available in a 16-bit DOS version and a 32-bit Windows version.

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Not related to the .JAR format, which is a Java Archive.

Programs that open J files
ARJ Software JAR
Updated 12/14/2006

File Type 3JPEG Image

2.3 (4 Votes)
CategoryRaster Image Files


This file is saved in a binary format, which requires a specific program to read its contents.

.J File Association 3

Compressed graphic that uses .JPEG image compression; may contain thousands of colors, which makes it a good format for storing digital photos; can use different levels of compression, but the more compression is used, the lower the quality of the resulting image.

More Information

Most JPEG files have a .JPG extension.

Programs that open J files
Updated 2/15/2007

About J Files

Our goal is to help you understand what a file with a *.j suffix is and how to open it.

All file types, file format descriptions, and software programs listed on this page have been individually researched and verified by the FileInfo team. We strive for 100% accuracy and only publish information about file formats that we have tested and validated.

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