File Decompiler: Java Class

Download Bytecode Viewer (open-source, actively maintained). It lets you switch between CFR, Procyon, FernFlower, and even a bytecode editor – invaluable for forensic work. Example Usage (CFR) # Decompile a single class java -jar cfr.jar MyClass.class Decompile entire JAR into a folder java -jar cfr.jar myapp.jar --outputdir ./src Handle obfuscated code better java -jar cfr.jar tricky.jar --renamedupmembers true --hidebridge false Final Verdict | Need | Best Tool | |------|------------| | Modern Java (8–21) | CFR | | Inside IntelliJ | FernFlower | | Quick GUI for legacy code | JD-GUI (with caution) | | Obfuscated/complex flow | Procyon | | All-in-one forensic GUI | Bytecode Viewer | ⚠️ Legal note : Decompiling code you don’t own may violate licenses or laws. Use only on code you have rights to – your own, open-source with compatible licenses, or for interoperability as allowed by law. Last reviewed: 2025 – still accurate for Java 21 and below.