JAR Decompiler

Browse and decompile Java .jar files directly inside VS Code. Open any class file and read its source instantly — with full editor features like syntax highlighting, go to definition, and search.

Features

• Browse JAR contents — tree view showing all packages, classes, and resources
• Decompile on demand — click any .class file to open it as readable Java source
• Two decompiler backends — CFR (fast, default) and Vineflower (better output for complex code)
• Automatic fallback — if CFR fails on a complex class, Vineflower is tried automatically
• Read non-class resources — view .properties, .xml, .MF, and other files inside the JAR

Usage

1. Right-click a .jar file in the Explorer and choose Open JAR File
2. The JAR Contents panel opens in the sidebar
3. Click any .class entry to decompile and view the source

You can also use the command palette: JAR Decompiler: Open JAR File.

Switching decompiler

Click the settings icon in the JAR Contents panel title bar, or open the command palette and run JAR Decompiler: Set Decompiler to toggle between CFR and Vineflower.

You can also set the default in settings:

"jarDecompiler.decompiler": "CFR"   // or "VINEFLOWER"

Requirements

• Java 11 or newer must be installed and accessible.
• By default the extension uses java from your PATH. You can override this in settings:

"jarDecompiler.javaPath": "/path/to/java"

WSL users

If you are running VS Code on Windows with the extension installed in WSL, set javaPath to the full Linux path of the Java binary, for example:

"jarDecompiler.javaPath": "/home/user/.sdkman/candidates/java/current/bin/java"

Extension Settings

Decompiler backends

Known limitations

• Decompiled output is read-only
• Highly obfuscated classes may not decompile cleanly

License

MIT