Open Source Java Disassemblers

BinExport is a disassembly export plugin developed by Google as part of the BinDiff ecosystem, designed for reverse engineering and binary analysis. It works with popular disassemblers including IDA Pro, Binary Ninja, and Ghidra, enabling the export of disassembly data into a structured Protocol Buffer format. This exported data can then be used for binary comparison, diffing, and advanced analysis tasks through BinDiff or other compatible tools. BinExport captures detailed information such as instructions, functions, control flow graphs, and metadata, providing a machine-readable representation of a program’s disassembled structure. It supports multiple export formats, including binary, text, and statistics outputs, and can be used interactively or via scripting (IDC, IDAPython, or Ghidra’s headless mode). The project includes complete build instructions for Linux, macOS, and Windows, ensuring reproducibility across platforms.

Dedexer is a disassembler tool for Android DEX files. The purpose is to create Jasmin-like source files from DEX files.

A open source java card virtual machine implementation. And also some part of the VM code can be used as part of kinds of tools such as javacard bytecode disassembler.

Q Disassembler is a flexible disassembly engine that aims to provide precise information about machine instructions while maintaining OS-independence and performance.

JReversePro is a Java Decompiler / Disassembler written in Java. Facility to view the ConstantPool contents is available. AWT, Swing and command-line versions are present.

small & symple disassembler, resource unpacker and flowchart graphical editor

Java Decompiler, Disassembler and Bytecode debugger. Decompiler supports Java 5 (e.g. generics, for-each loops etc). Debugger allows user to step through each bytecode and view program state. Contains Swing GUI.

JEST will be the Java bytecode engineering Swiss-Army Jackhammer. It will include a disassembler, class browser, obfuscator, optimizer, class editor, and bytecode debugger, and have an intuitive GUI.

JasminParser is a Jasmin (Java Assembler, .j file) compiler based on the Apache BCEL. JasminParser provides a disassembler and an assembler to convert java classes and jasmin files to each other.

Lilac is a tool suite, which contains an assembler and a disassembler for the JVM (Java Virtual Machine) bytecode. The assembler takes textual representations of Java classes, written in an assembler-like syntax, and converts them to binary Java class files, which can be loaded into JVM. The disassembler takes binary Java class files and creates out of them assembler files suitable for the assembler. In general (except for some very rare cases) Lilac tools allow a perfect round-trip, that is, if you disassemble a class file and then assemble it again, without making any changes, you'll get the original file.

Emulator of the ancient 8 bit microprocessor ISP-8A 500D/600D or more common "SC/MP" from National Semiconductor. The download contains all sources plus an executable Java Jar file to start right away. Some SC/MP hex dump examples are provided in directory "/etc" as well. The download also contains unit tests and some helping documentation (also in /etc). You may slow down the CPU operations, displaying the CPUs status register as LEDs, to watch the CPU working with its registers. The emulator also contains a VDU (video display unit) output / ASCII input simulation. There are some demos in /etc. And have a look to the NIBL / TINY BASIC interpreter in the TINYBASIC folder, most of the code is over 40 years old. Have fun, Theo Heinrichs

dxcut is a library for reading, editing, and writing dex and odex files which contain the class definition and Dalvik bytecode used by the Android operating system. This project includes a disassembler/decompiler, dex optimizer, and hooking utils.

jbytecode is a Java bytecode disassembler/assembler written in Python. Dissasembly code is aligned with Java bytecodes in the class file so modification and re-assembly is always possible, even when class is obfuscated.

This is a swf-decoder and disassembler