Browse free open source Java Compilers and projects below. Use the toggles on the left to filter open source Java Compilers by OS, license, language, programming language, and project status.
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A native Windows port of the GNU Compiler Collection (GCC)
MinGW: A native Windows port of the GNU Compiler Collection (GCC), with freely distributable import libraries and header files for building native Windows applications; includes extensions to the MSVC runtime to support C99 functionality. All of MinGW's software will execute on the 64bit Windows platforms.
Command-line and GUI tools for producing Java source code from Android Dex and apk files. Decompile Dalvik bytecode to java classes from APK, dex, aar, aab and zip files. Decode AndroidManifest.xml and other resources from resources.arsc. Deobfuscator included. Be aware, Android Studio can interfere with jadx debugger, so it is better to close it before attaching to the process in jadx. Smali debugger, check wiki page for setup and usage. View decompiled code with highlighted syntax.
unluac is a decompiler for Lua 5.0 through 5.4. It runs on Lua chunks that have been compiled with the standard Lua compiler. It requires that debugging information has not been stripped from the chunk. (By default, the Lua compiler includes this debugging information.)
This program is written in Java. A JAR package is available in the downloads section so you don't have to compile it. It runs from the command line and accepts a single argument: the file name of a Lua chunk. The decompiled code is printed to the standard output.
Here is an example usage of unluac:
java -jar unluac.jar myfile.lua > myfile_decompiled.lua
The current version also has pretty good support for Lua 5.0 and Lua 5.1. Support for later versions is also good if the code doesn't use too many gotos.
JD-GUI is a standalone graphical Java decompiler that allows users to reconstruct and explore source code from compiled .class files. It provides an intuitive interface for browsing decompiled code, making it easier to inspect methods, fields, and class structures without access to original source files. The tool is widely used for reverse engineering, debugging, and understanding third-party libraries. It supports opening individual files as well as entire archives such as JARs, enabling efficient navigation across large codebases. JD-GUI emphasizes simplicity and accessibility, allowing developers to quickly analyze compiled Java applications. It integrates with standard Java tooling and can be extended with additional modules. Overall, it is a practical utility for developers working with bytecode-level artifacts.
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A reverse engineering suite (decompiler, editor, debugger and more)
Some of Bytecode Viewer features are that it provides Java Decompiling with Six different decompilers (DJ-GUI/Core, Procyon, CFR, Fernflower, Krakatau, and JADX-Core). Bytecode Decompiling with CFIDE. Android APK integrated with Dex2Jar. Securely launch Java applications and insert hooks via EZ-Injection. Scan for malicious code with the Malicious Code Scanner plugin. Export as DEX, Jar, Class, Zip or Java Source File. Open Android APKs, Android DEX, Java Class Files and Java Jars. (WAR & JSP Support!). Extensively configurable, over 100+ settings! Works seamlessly with all Operating Systems. Integrates BCV into Windows by installing it, it'll associate all .class, .dex and .apk to open with BCV. You can view Jar & APK Resources with ease by APKTool.jar integration. It is 100% free and open sourced under GPL v3 CopyLeft.
Decompiler from Java bytecode to Java, used in IntelliJ IDEA
Fernflower is an open-source Java decompiler originally developed by JetBrains that takes compiled Java bytecode and reconstructs readable source code, helping developers understand, debug, and recover lost Java code from .class files. It works by analyzing the structure of bytecode and inferring higher-level constructs like loops, conditionals, generics, and exception handling to produce Java source that is as close as possible to what a human would have written, making it useful for both reverse engineering and educational purposes. Fernflower is integrated into popular Java IDEs and tools where decompilation is needed, and its robust analysis handles a wide range of language features introduced across multiple Java versions. Because it outputs clean, structured, and often compilable code, developers use it for auditing binaries, exploring third-party libraries without source, and recovering parts of legacy systems where source was lost or unavailable.
JPEXS Free Flash Decompiler is open-source Flash SWF decompiler
JPEXS Free Flash Decompiler is a free, open-source application for analyzing, editing, and extracting content from Adobe Flash SWF files. It enables users to inspect compiled Flash applications and recover resources such as images, sounds, fonts, shapes, and scripts. The software supports ActionScript 1, 2, and 3 decompilation, allowing developers to examine and modify embedded program logic. Users can replace multimedia assets, edit text, and modify SWF structures without access to the original project files. It also supports converting SWF content into FLA format for further editing. Its integrated interface provides resource previews, script editing, and multiple export options. Built with Java, it runs on Windows, macOS, and Linux and is useful for software preservation, reverse engineering, and Flash content recovery.
Translates state machine into a target programming language.
SMC takes a state machine stored in a .sm file and generates a State pattern in 14 programming languages. Includes: default transitions, transition args, transition guards, push/pop transitions and Entry/Exit actions. See User Manual for more info.
WinXP, Vista, Win7, linux, OpenSolaris native port of the BSD PSPSDK (ps2dev.org), with freely distributable import libraries and header files (DevPaks) for building cross compiled homebrew Sony PSP (PlayStation Portable) applications.
IKVM.NET is a JVM for the Microsoft .NET Framework and Mono. It can both dynamically run Java classes and can be used to convert Java jars into .NET assemblies. It also includes a port of the OpenJDK class libraries to .NET.
JikesTM is a compiler for the JavaTM language. The Jikes project strives for strict adherence to the Java Language and Java Virtual Machine Specifications. Jikes' most popular feature is it's extremely fast compile speed.
Jasmin is a Java Assembler. It takes ASCII descriptions for Java classes, written in a simple assembler-like syntax. It converts them into binary Java .class class files suitable for loading into a Java Virtual Machine implementation.
A Java Virtual Machine for OpenJDK that's optimized for small footprint, fast start-up, and high throughput. Builds on Eclipse OMR and combines with the Extensions for OpenJDK for OpenJ9 repo. We're not sure which route you might have taken on your way here, but we're really pleased to see you! If you came directly from our website, you've probably already learned a lot about Eclipse OpenJ9 and how it fits into the OpenJDK ecosystem. Eclipse OpenJ9 is an independent implementation of a Java Virtual Machine. "Independent implementation" means it was built using the Java Virtual Machine specification without using any code from any other Java Virtual Machine. The OpenJ9 JVM combines with the Java Class libraries from OpenJDK to create a complete JDK tuned for footprint, performance, and reliability that is well suited for cloud deployments. The original source contribution to OpenJ9 came from the IBM "J9" JVM which has been used in production by thousands of Java applications.
JSmooth creates standard Windows executable files (.exe) that smartly launch java applications. It makes java deployment much smoother and user-friendly, as it is able to find and run Java VMs by itself, or help the user get one if none are available.
JCppEdit is a free as well as "best IDE for Beginners" and is your one-stop IDE for all your coding needs. Whether you need to finish your Java project or submit your first HTML web page or perhaps have a need to code in C language while executing a java program into a Java IDE, JCppEdit will help you achieve your goals easily.
Exploring your project and detecting an error in your code is much easier. You will not waste time detecting errors before compiling codes because you will get a real-time notification whenever you are making any mistake in your C, C++, and Java codes.
You can also create multiple projects, delete, rename, cut and copy multiple files and folders in your project folder using project explorer. The programming languages that can be compiled and executed include; C, C++, Java, Java applet, C graphics, HTML, CSS, JavaScript and XML.
If you are looking for a hassle-free, coding experience, then JCppEdit is the best option for you. The smooth interface and lig
X10 is a class-based, strongly-typed, garbage-collected, object-oriented language. To support concurrency and distribution, X10 uses the Asynchronous Partitioned Global Address Space programming model (APGAS). This model introduces two key concepts -- places and asynchronous tasks -- and a few mechanisms for coordination. With these, APGAS can express both regular and irregular parallelism, message-passing-style and active-message-style computations, fork-join and bulk-synchronous parallelism.
Both its modern, type-safe sequential core and simple programming model for concurrency and distribution contribute to making X10 a high-productivity language in the HPC and Big Data spaces. User productivity is further enhanced by providing tools such as an Eclipse-based IDE (X10DT). Implementations of X10 are available for a wide variety of hardware and software platforms ranging from laptops, to commodity clusters, to supercomputers.
Source code of APK Explorer & Editor (AEE), an open-source tool
APK Explorer & Editor is a free, open-source Android application designed for inspecting and modifying APK files. It allows users to browse the contents of installed applications or APK packages stored on their devices. The software can extract resources such as icons, fonts, graphics, and XML files. Its integrated editors support modifying text and binary XML resources. Users can replace or delete resources and reassemble modified Smali code into DEX files. The application also includes tools for decoding resource tables and managing split APKs. Modified applications can be rebuilt and signed for installation. APK Explorer & Editor provides a portable toolkit for Android application inspection, customization, and package management.
Portable version of the multifunctional development platform Eclipse.
With this portable version of Eclipse, you can develop software directly from your removable mass storage device, even without admin rights.
To get started, please visit the Eclipse Portable wiki: https://sourceforge.net/p/eclipse-neon-portable/wiki
GitHub: https://github.com/Berny23/eclipse-portable
Thank you for over 180,000 Downloads!
Please note:
A few months ago, I completely switched to Linux (now Arch btw). So, I'll be no longer active creating portable apps for Windows.
The aim of this project is to develope a decompiler for java which is platform independent and has options to obfuscate the class file also.
The project takes class file as input and decompiles it and provides the source file.
The Open Fortran Project (OFP) provides a Fortran 2008 compliant parser and associated tools. These tools provide a Java and C API for actions called when parser rules are completed. It also provides Fortran interfaces to the OpenCL runtime (new).
IMPORTANT NOTICE: The Open Fortran Project has switched to using a parser based on SDF (Syntax Definition Formalism). Please consider using our new work at https://github.com/OpenFortranProject/ofp-sdf. While the SDF parser is not as advanced as the ANTLR-based parser, it provides much more capabilities, including a term rewriting system for creating a Fortran AST (Abstract Syntax Tree) using Stratego/XT (see http://strategoxt.org) and other custom program transformations.
The OFP ANTLR-based parser is no longer under active development.
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