.j

File Type 1 Generic IconJava Source File
File Format Standard (developed by Oracle)
Usage Open manually; may be referenced by an application
Rank ★ ☆ ☆  Uncommon
Description

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.

Java source files most often have a .JAVA extension.

Open With
Windows

IconOracle Java Virtual Machine

IconEclipse IDE for Java Developers

IcongVim

macOS

IconOracle Java Virtual Machine

IconEclipse IDE for Java Developers

Unix

IconOracle Java Virtual Machine

IconEclipse IDE for Java Developers

Iconjavac

Updated 2007
File Type 2 Generic IconJAR Archive
Rank ★ ☆ ☆  Uncommon
Description

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.

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

Open With
Windows

IconARJ Software JAR

Updated 2007
File Type 3 Generic IconJPEG Image
File Format Standard
Usage Open manually
Rank ★ ☆ ☆  Uncommon
Description

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.

Most JPEG files have a .JPG extension.

Open With
Windows

IconAny picture viewer

IconAny Web browser

macOS

IconAny picture viewer

IconAny Web browser

Updated 2007
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