JD-GUI is an open-source, standalone graphical Java decompiler, available on Kali Linux at /usr/bin/jd-gui, designed for reverse-engineering compiled Java applications by extracting readable source code from .class or .jar files. Developed by Emmanuel Dupuy and packaged for Kali by Sophie Brun, JD-GUI provides a user-friendly GUI to browse class hierarchies, view decompiled Java code, and save sources as .java files. Ideal for cybersecurity researchers, Android developers, and ethical hackers, it supports malware analysis, code auditing, and vulnerability research. Often paired with tools like Dex2Jar, JD-GUI simplifies Java bytecode analysis.
