How to Convert .class to .java (Explained)

Learn how to convert compiled Java .class files back into .java source code using decompilers — online, command-line, and IDE methods.

What Is a .class File?

Method 1: Convert Online (No Install)

Method 2: CFR (Command-Line)

Method 3: `javap` — Bytecode Disassembly (Not Full Source)

Method 4: IDE Decompilation (IntelliJ IDEA)

Understanding the Decompiled Output

Checking the Java Version of a .class File

Full Workflow: Extract Class from JAR, Decompile, Edit, Replace

Summary