Browse free open source Java System Software and projects below. Use the toggles on the left to filter open source Java System Software by OS, license, language, programming language, and project status.

  • Paessler - Monitor Your Whole Network in Minutes Icon
    Paessler - Monitor Your Whole Network in Minutes

    Auto-discovery finds your devices and deploys pre-configured sensors instantly. No project plan required, just visibility from day one.

    Waiting weeks for a monitoring rollout isn't an option when infrastructure doesn't stop running. PRTG's auto-discovery scans your network and suggests from over 200 pre-configured sensor types, so you're watching servers, applications and devices within minutes, not after a multi-week deployment. Enterprise-strength monitoring, without the enterprise complexity. Start your free trial today.
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  • Demo Series - Small Business Backup By Veeam Icon
    Demo Series - Small Business Backup By Veeam

    Learn how to protect your Microsoft 365 data, with simple, actionable tips today.

    Watch this on-demand demo series and learn how to protect your Microsoft 365 data with clear, simple, actionable steps that are easy to implement for businesses of all sizes.
    Watch Demo Series
  • 1
    ASAP - Another Slight Atari Player
    ASAP (Another Slight Atari Player) plays and converts 8-bit Atari music (*.sap, *.cmc, *.mpt, *.rmt, *.tmc, ...) on modern computers and mobile devices.
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    Downloads: 88 This Week
    Last Update:
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  • 2

    iPAQ 200/210/211/212/214 Android Porting

    Porting Android to the iPAQ 200/210/211/212/214 or equilivalent

    Porting Android to the iPAQ 200/210/211/212/214 or equilivalent. It has a 4-inch VGA Screen (TFT LCD display), resistive touchscreen, WiFi, Bluetooth, SD/MMC, CF. Originally it is running Windows Mobile 6 Classic. For help, see README files and the wiki. This project is in Alpha state, that means it is not suitable for daily usage unless developing for the project. NOT FOR THE FAINTHEARTED AND/OR COMPUTER IDIOTS!
    Downloads: 58 This Week
    Last Update:
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  • 3
    JNode is a Java New Operating system Design Effort. JNode is a simple to use and install Java operating system for personal use on modern devices. Any java application runs on it, fast and safe. See our homepage for additional information.
    Downloads: 62 This Week
    Last Update:
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  • 4
    Nesoid

    Nesoid

    NES emulator for Android phones

    This project is based on sources, published by original Nesoid developer, who in turn used code of GPFCE, forked from FCEUltra, currently incarnation of which is known as FCEUX. Help and suggestions are welcome. This project has been abandoned in favor of the RetroArch, another awesome free software emulator (which has much better NES support and is more actively developed): http://www.libretro.com/.
    Downloads: 45 This Week
    Last Update:
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  • Ship Agents Faster Icon
    Ship Agents Faster

    Transform your applications and workflows into powerful agentic systems at global scale.

    Gemini Enterprise Agent Platform lets you rapidly build, scale, govern and optimize production-ready agents grounded in your organization's data. The platform enables developers to build custom or pre-built agents for virtually any use case. New customers get $300 in free credits.
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  • 5
    Apple Disk Transfer ProDOS

    Apple Disk Transfer ProDOS

    Transfer disks and disk images between the Apple II and the real world

    Apple Disk Transfer ProDOS (ADTPro) transfers classic 8-bit Apple disk images over a serial, ethernet or audio link to a more modern computer. Based on the seminal ADT, ADTPro can transfer any ProDOS- or SOS-visible volume.
    Downloads: 17 This Week
    Last Update:
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  • 6
    GameBoid

    GameBoid

    Gameboy Advance emulator for Android phones

    This project is based on sources published by original GameBoid developer, who in turn used code of gpSP2X, based on gpSP. Help and suggestions are welcome. This project is abandoned in favor of RetroArch: http://www.libretro.com/. Seriously, check that one out!
    Downloads: 22 This Week
    Last Update:
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  • 7
    z390 Portable Mainframe Assembler

    z390 Portable Mainframe Assembler

    z390 Portable Mainframe Assembler and Emulator

    z390 Portable Mainframe Assembler and Emulator
    Downloads: 5 This Week
    Last Update:
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  • 8
    Cambridge Z88

    Cambridge Z88

    Software development for 4Mb portable, using Z80 CPU and AA batteries

    This project is for the portable computer "Cambridge Z88", produced by Sir Clive Sinclair (of ZX Spectrum fame). We continue to support software development (ROM, 3rd party apps on memory cards and desktop applications). We have moved to https://cambridgez88.jira.com/wiki (development, source code and documentation). However, we continue to publish files for download here.
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    Downloads: 14 This Week
    Last Update:
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  • 9
    GBCoid

    GBCoid

    Gameboy and Gameboy Color emulator for Android phones

    This project is based on sources published by original GBCoid developer, who in turn used code of gnuboy. Help and suggestions are welcome. This project has been abandoned in favor of RetroArch, another awesome free software console emulator (which is also actively developed): http://www.libretro.com/.
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    Downloads: 7 This Week
    Last Update:
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  • Train ML Models With SQL You Already Know Icon
    Train ML Models With SQL You Already Know

    BigQuery automates data prep, analysis, and predictions with built-in AI assistance.

    Build and deploy ML models using familiar SQL. Automate data prep with built-in Gemini. Query 1 TB and store 10 GB free monthly.
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  • 10

    jArt Java Operating System

    IA-32 operating system with Java virtual machine embedded into the ker

    IA-32 operating system with Java virtual machine embedded into the kernel. Part of the kernel is written in Java. Only Java applications can run on this system. jArt VM is a stand-alone virtual machine that interprets java bytecode. It can run under Linu
    Downloads: 10 This Week
    Last Update:
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  • 11
    JBit
    JBit is small java application for mobile phones (MIDlet) that gives you a programmable 8-bit microcomputer. With JBit, you can edit, save, run and debug assembly (6502) programs directly on your phone.
    Downloads: 5 This Week
    Last Update:
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  • 12
    Apple Game Server 3.1

    Apple Game Server 3.1

    Upload games to legacy apple // computers via serial and no floppies!

    This java (version 6 or higher) program allows you to send games directly to an old apple // computer with no need for floppies, only a serial cable. No hardware modification is necessary, you only need a working serial connection. A cousin of this project can be found here: http://asciiexpress.net/gameserver/ (Thanks Egan!)
    Downloads: 2 This Week
    Last Update:
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  • 13
    Interlocking system for modular model railroading. The goal is the development of hard- and software for an model interlocking interfacing on the one hand to the model railroad and on the other to the model of the userinterface of an real interlocking.
    Downloads: 3 This Week
    Last Update:
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