Classpy

Classpy is a GUI tool for investigating Java class file, Lua binary chunk, Wasm binary code, and other binary file formats.

Inspiration

This tool is mainly inspired by javap and JavaClassViewer. I reinvent the wheel for the following two reasons:

1. Learn Java class file format and bytecode through parsing it
2. Try JavaFX 8

Features

• Understands class files described by JVMS9
• Supports Lua 5.3 binary chunk format
• Supports Wasm binary format
• Supports Bitcoin raw block and transaction format
• Displays parsed binary file as tree and hex text
• The corresponding hex text is highlighted when you select a tree node

Quick Start

Just for macos with brew

• Install

brew tap guxingke/repo && brew install classpy

• Try
  • open default gui window

  classpy

  • open gui window with args

  echo "public class HelloWorld { public static void main(String[] args) { System.out.println(\"Hello World\"); } }" > HelloWorld.java
  $JAVA_HOME/bin/javac HelloWorld.java
  
  classpy HelloWorld.class

Requirements

Java 15 (checkout branch java8 if you stuck on Java 8)

Build

cd path/to/classpy
./gradlew fatJar
# java -jar path/to/classpy/classpy-gui/build/libs/classpy-fat-jar-0.10.0.jar

Run

cd path/to/classpy
./gradlew run

Screenshots