Robocode News

Robocode 1.11.1 released

2026-07-13T15:38:08.972+02:00

Version 1.11.1 (13-Jul-2026)

Bugfix

#94: Avoid misleading priority warnings for system events. System events retain their fixed priority instead of being clamped to the 0–99 range used by robot-defined events.

Changes

Updated LiteRumble links and RoboRumble configuration URLs to https://rumble.robowiki.net/.
Updated to use Eclipse JDT 3.46.0.

Download Robocode 1.11.1 from here

Robocode 1.11.0 released

2026-06-06T14:07:37.666+02:00

Version 1.11.0 (06-Jun-2026)

Changes

Installer overhaul: Refactored the monolithic AutoExtract installer (844 lines) into 5 focused classes (Installer, InstallerDialog, Extractor, ShortcutManager, OsUtil).
Reduced confirmation dialogs from 5 user prompts down to 1 — a single "Install to" dialog with Proceed/Cancel.
Removed license agreement dialog, start-menu shortcut prompt, and Windows file associations prompt.
Removed Windows .battle/.br file association registration (rarely used, required admin privileges).
Removed legacy code: Win 9x/ME command.com path, obsolete .robotcache migration, fragile self-cleanup hacks.
Windows shortcuts are now always created without prompting.
Improved code quality: try-with-resources, StringBuilder, proper error handling, fixed spinner animation bug.

Bugfix

#89: Prevent a single fire command from spawning duplicate bullets with the same ID
- A single setFire() call could spawn multiple bullets sharing the same bullet ID, which could cause issues with bullet tracking and battle accuracy.
- Thanks go to Pavel Savara for fixing this ❤️. Sharp-eyed fix!

Download Robocode 1.11.0 from here

Battle Runner released for Robocode Tank Royale 0.37.0

2026-03-04T22:40:00.000+01:00

I have just made a new release of Robocode Tank Royale 0.37.0, which contains the new Battle Runner 🎉 https://robocode.dev/api/battle-runner

The Battle Runner API lets you run Robocode Tank Royale battles programmatically from any JVM application — no GUI required. Use it for automated testing, benchmarking, tournament systems, or any scenario where you need headless battle execution.

Tank Royale Viewer

2026-02-16T15:37:00.002+01:00

🖥️ Visualize Robocode battles in style!

Check out the Tank Royale Viewer by Jan Durovec – an amazing web-based viewer for watching Robocode Tank Royale matches in real-time! 🚀

Perfect for tournaments, analyzing strategies, and displaying battles on big screens! ⚡

👉 https://github.com/jandurovec/tank-royale-viewer

📚 Introducing: The Book of Robocode 🤖

2026-01-31T21:55:00.003+01:00

Introducing: The Book of Robocode

The Robocode community now has a comprehensive guide for mastering bot programming!

The Book of Robocode is a free, open-source resource covering everything from your first bot to advanced competitive strategies.

🎯 What's Inside

Step-by-step tutorials for beginners
Movement strategies (circular, wave surfing, and more)
Targeting techniques (linear, circular, pattern matching)
Radar and energy management
Real code examples for both Robocode and Robocode Tank Royale

🔗 Links

🌐 Read it online: book.robocode.dev

💻 GitHub: robocode-dev/book-of-robocode

✨ Features

📖 Progressive learning path from novice to expert
🔬 Math and are physics explained clearly
🏆 Competition-ready strategies
🤝 Built on 20+ years of RoboWiki knowledge

Whether you're writing your first bot or aiming for the top of the RoboRumble rankings, this book has something for you!

Contributions welcome — open an issue or PR if you'd like to help expand the content. 🚀

Happy robocoding! 🎮

Robocode 1.10.1

2025-12-09T19:52:00.004+01:00

Version 1.10.1 (09-Dec-2025)

Bugfix

#71: Replaced Thread.stop() call with Thread.interrupt() in the RobotThreadManager
- The Thread.stop() call has been removed as of Java 21, so the old call to stop() would cause the rest of the battle to be aborted; e.g., if you were running 100 rounds, but after the second a robot's thread needs to be terminated, then that would abort the rest of the rounds. By swapping in interrupt, the thread should still terminate, but gracefully.
- Thanks go to Jeremiah Blanchard for fixing this ❤️. Nice catch!

Changes

Improved documentation and comments with all sample bots.
Updated libraries (dependencies) to the latest versions (including Eclipse Compiler for Java and Codesize).

Download Robocode 1.10.1 from here

Robocode 1.10.0

2025-06-04T21:20:00.001+02:00

Version 1.10.0 (04-Jun-2025)

Robocode's code around RobocodeSecurityManager has been refactored to ensure compatibility with Java 24 and newer versions, even after the retirement of the Security Manager in Java 24. Read more here.
Additionally, Robocode remains fully functional on older Java versions, from Java 8 onward.

Changes

Java 24 support: Implemented new security mechanisms that work with Java 24+ while maintaining compatibility with Java 8+.
Versioning update: Adopted Semantic Versioning starting with version 1.10.0.

Download Robocode 1.10.0 from here

Robocode 1.9.5.6

2025-05-31T00:37:00.003+02:00

Version 1.9.5.6 (30-May-2025)

Bugfix

Lim Sim Yee found and fixed the following vulnerabilities. Thank you for the PRs ❤️

Vulnerabilities fixes:

Bug #67: The CacheCleaner contained a Directory Traversal Vulnerability when deleting files (recursively).
Bug #68: Fix for Insecure Temporary File Creation.
But #70: Fix Integer Overflow Vulnerability in Buffer Write Method.

Download Robocode 1.9.5.6 from here

Robocode 1.9.5.5

2025-03-30T00:04:00.002+01:00

Version 1.9.5.5 (29-Mar-2025)

Changes

Robocode cannot run with Java 24, which implemented JEP 486: Permanently Disable the Security Manager.
- Robocode has its own security manager built on top of Java's Security Manager, which has now been removed with Java 24.
- Robocode will not start up when running Robocode on Java 24 and newer. Instead, an error message is written out that Robocode does not support Java 24.
- Fixing this issue requires a big rewrite of large parts of the security mechanisms in Robocode to prevent robots from doing harm on the system and from cheating against other competitor robots in battles.
- Use Java 23 or an older version of Java instead, or head over to the new platform for Robocode: Robocode Tank Royale.

Download Robocode 1.9.5.5 from here

Robocode 1.9.5.4

2024-09-30T19:39:00.001+02:00

Version 1.9.5.4 (30-Sep-2024)

Bugfix

The built-in Eclipse Compiler for Java (ECJ) could not be found.

Download Robocode 1.9.5.4 from here

Robocode 1.9.5.3

2024-09-11T22:41:00.005+02:00

Version 1.9.5.3 (11-Sep-2024)

Bugfix

[#66]: Fixed an issue where Robocode would not start when executing the robocode.sh script for Linux and macOS due to this error: java.lang.UnsupportedOperationException: The Security Manager is deprecated and will be removed in a future release
- Thanks goes to @scientificworld for this fix. 😊

Improvements

Upgraded built-in Eclipse Compiler for Java to version 3.39

Download Robocode 1.9.5.3 from here

New tutorials for Robocode

2024-07-17T14:36:00.002+02:00

I have spent some time of my summer vacation to write a tutorial named Getting Started, if you are new to Robocode Tank Royale.

In addition, I wrote a tutorial named Beyond the Basics, which any Robocoder should read to advance his/her skills for making more advanced robots. This tutorial is written for the Tank Royale version, but applies the original version of Robocode as well.

Happy Robocoding! ❤️

Robocode 1.9.5.2

2023-10-24T22:05:00.001+02:00

Version 1.9.5.2 (24-Oct-2023)

Bugfix:

Fixed Throwable: java.lang.LinkageError: loader constraint violation: when resolving method issue in the RobotClassLoader.

Download Robocode 1.9.5.2 from here

Robocode 1.9.5.1

2023-07-30T14:19:00.005+02:00

Version 1.9.5.1 (30-Jul-2023)

Bugfix:

Fixed ClassCastException with URLClassLoader when accessing ClassLoader.getSystemClassLoader() on Java version newer than Java 8 and running with -DNOSECURITY=true.

Improvements

Updated all .bat, .sh, and .command files so the _JAVA_OPTIONS is now set automatically regardless of the Java version.
Updated dependencies.

Download Robocode 1.9.5.1 from here

Robocode 1.9.5.0

2023-02-26T11:40:00.001+01:00

Version 1.9.5.0

Please note that you should be aware of which version of Java you are using for running Robocode. Otherwise, Robocode might not start. You can check this by running this command in a terminal: java -version. If you are running on a Java version older than version 12, you need to uncomment or remove this line in the robocode.bat or robocode.sh file:

_JAVA_OPTIONS="-Djava.security.manager=allow"

If you are running on Java 12 or newer, then the above line is required, and should not be removed!

Bugfix:

Bug-418: Excluded bots are removed from LiteRumble. Thanks to Xor for this fix! :)

Improvements

Updated all .bat, .sh, .command files with detailed information about various settings. Now you only need to comment out the line containing _JAVA_OPTIONS="-Djava.security.manager=allow" if you run on Robocode on a Java version older than version 12, and you can disable Direct3D on Windows, and also set the rasterizer used in Direct3D. Have a look at robocode.bat and robocode.sh if you want to see the details.
Robocode does not touch any sun.java2d programmatically anymore as these give different results on different hardware (obviously). So the user needs to set these explicitly as options when starting up Robocode. Go to this page if you want to experiment with
these settings.

Download Robocode 1.9.5.0 from here

Robocode 1.9.4.9

2023-01-28T12:18:00.006+01:00

Version 1.9.4.9 (28-Jan-2023) Fixed "no security" and HiDPI

Bugfixes

NOSECURITY=true could cause a ClassNotFoundException for the robots.
Rendering issue on Windows when setting sun.java2d.ddoffscreen=false. Hence, this setting has been removed.
If the NOSECURITY or EXPERIMENTAL property has been set to true, a warning is now printed out to standard out.
Re-fix Bug-394 by actually supporting HiDPI. Thanks to Xor for this fix! :)

Download Robocode 1.9.4.9 from here

Robocode 1.9.4.8

2022-11-29T20:39:00.000+01:00

Version 1.9.4.8 (29-Nov-2022) Reworked Disabling Security Manager

Bugfixes

Rendering issues on Windows using accelerated hardware, by setting this Java properties:
- sun.java2d.d3d=false (turn off use of Direct3D)
- sun.java2d.ddoffscreen=false (turn of Direct Draw off-screen)
- sun.java2d.noddraw=true (no use of Direct Draw)
- sun.java2d.opengl=True
Adding -source 1.5 to the ECJ compiler options to prevent "...only available if source level is 1.5 or greater" error when compiling with ECJ.

Improvements

Security Manager: When setting the NOSECURITY=true (e.g. via the -DNOSECURITY=true property in the java command-line), then internal security manager of Robocode is now totally disabled, and falling back on the default security manager used in Java.
- This fixes issues with the class loader not being able to find classes resulting in ClassNotFoundExceptions, and other issues as well.
Updated built-in Eclipse Compiler for Java (ECJ) to version 3.26 (June 2021), which is the last version of ECJ capable to run on Java 8 (newer ECJ versions requires Java 11 as minimum).

Download Robocode 1.9.4.8 from here

Robocode 1.9.4.7

2022-08-06T12:29:00.006+02:00

Version 1.9.4.7 (05-Aug-2022) System.getenv support

Changes

#35 System.getenv is now allowed and can now be called without throwing a security exception. Hence, the robot will not be banned from battles when using System.getenv.

Download Robocode 1.9.4.7 from here

Robocode 1.9.4.6

2022-06-15T23:56:00.001+02:00

Version 1.9.4.6 (15-Jun-2022) The Java 18 support release

Newer versions of Java is making things harder for the codebase of Robocode.

With Java 18 (JEP 411), the Security Manager is disabled by default, but can be allowed by the user from the command line. Hence, with this version of Robocode, the -Djava.security.manager=allow system property has been added to the script for making it possible to run Robocode on Java 18. Note that this is just a work-around, as the Security Manager will be permanently removed from Java at some point in the future when newer major versions of Java are released.

This is a big concern for Robocode, which uses the Security Manager to control access to various resources between robots running on the same JVM. And currently, no good substitute exists for replacing the Security Manager (or find a good way to remove it) from Robocode without breaking things.

Bugfix

Java 18 fix: Robocode could not run on the newest Java 18 due to the terminally deprecated Security Manager.
- The Security Manager is now explicitly being allowed to run with the .bat, .sh, and .command files by adding setting this system property: -Djava.security.manager=allow.
Give bots without rank highest priority in the LiteRumble (RoboRumble). Thank you Xor for this fix! :)

Download Robocode 1.9.4.6 from here

Robocode 1.9.4.5

2022-03-22T21:08:00.004+01:00

Version 1.9.4.5 (22-03-2022)

Bugfix

Fixed java.io.IOException: Stream Closed when auto-recording is enabled.
A mystic word on was written to the console.

Download Robocode 1.9.4.5 from here

Robocode 1.9.4.3

2021-09-05T12:37:00.000+02:00

Version 1.9.4.3 (04-09-2021)

Changes

Chocolatey installer is now provided for Windows.
- https://community.chocolatey.org/packages/robocode
- Install by choco install robocode
Roborumble could now override RUMBLE_USER, RUMBLE_PARTICIPANTSURL, RUMBLE_UPDATEBOTSURL, RUMBLE_RESULTSURL, RUMBLE_RATINGSURL via environment variables. Fixed to not clash with system USER env variable.
Updated ReadMe file.
Updated link to Java API documentation.

Bugfix

Bug-415: Loading pre-loaded data 1.9.4.2
- Fixed robot naming to be compatible with existing robots
- Thanks go to Alex Schultz (Rednaxela) for fixing this issue. :)
Installer (dos2unix): more reliable way to move files
- Thank you dshatov (GitHub) for this fix. :)
The classpath in the compiler setting does not include the path to rt.jar anymore, which caused compiler errors.

Download Robocode 1.9.4.3 from here

Robocode 1.9.4.2

2021-05-10T21:12:00.002+02:00

Version 1.9.4.2 (10-05-2021)

Changes

A robot index has been added to all robot in the format name + (index). This is change was made to fix various issues in e.g. team bots and make the internal logic simpler.
Improved the API documentation for the TeamRobot and Droid team robots.

Bugfix

Fixed getTeammates() that returned the wrong names and isTeammate() that returned false for teammates.

Download Robocode 1.9.4.2 from here

Robocode 1.9.4.1

2021-04-09T21:36:00.002+02:00

Version 1.9.4.1 (09-04-2021)

This release comes with lots of improvements. First and foremost, the old Maven build setup has been replaced with a Gradle build setup, and we moved to use IntelliJ IDEA for developing Robocode. The Robocode artefacts can also be uploaded to Sonatype's Maven Repository using Gradle.

In addition, a bug fix has been made for ramming, but a lot of other improvements were made for easy testability.

And a RoboRumble client has also been published as Docker image as well.

All credits go to Pavel Savara that has made a big effort into this release. :)

Please note that with this release the .Net plugin has been removed from Robocode. It was based on .Net Framework 3.5 and the required toolchain for building the plugin and the documentation for it had got some serious issues as well.

Changes

Bug-414 Fixed bug in ramming: when robots collide, they should and do change position. But the bullets were still hitting original place in the next turn, as if the robot was not moved by collision.
Robot painting to screen per default could be enabled by -DPAINTING=true
Made installer compatible with headless systems. Made default classPath lib/* for startup scripts.
Improve testability:
- Moved robocode.control.RobotTestBed.
- RoundStartedEvent.getRobotObjects() is available on Control API. Useful for white-box testing of robot state.
- Exceptions in the robot are now propagated to unit test. See test.robots.TestThrowing.
- Exceptions in the robot are now propagated to BattleErrorEvent of control API when -DTESTING=true
- Improved Robot and Bullet toString() so that it displays approximate cardinal direction, like N,NE,E,SE,S,SW,W,NW
- Added Utils.assertNotNull(), Utils.assertEquals(), Utils.assertTrue(), Utils.assertNear() for testing comfort.
- Bullet IDs are now more unique.
- Unit test is aborted on robot exception.
- Control API could now take screenshots.
- Unit test could enable taking screenshots when exception or asset occurs. See RobotTestBed.isEnableScreenshots()
- Robots could be statistically tested against multiple opponents. For example see net.sf.robocode.test.robots.TestScore
Roborumble could now override USER, PARTICIPANTSURL, UPDATEBOTSURL, RESULTSURL, RATINGSURL via environment variables.
Published Roborumble client as docker image to https://hub.docker.com/r/zamboch/roborumble with the above environment variables available.

Version 1.9.4.0 (15-02-2021)

Changes

Migrated from Maven to Gradle.
Migrated from Eclipse to Idea.
Published to Maven Central.

Download Robocode 1.9.4.1 from here

Robocode 1.9.3.9

2020-04-20T20:47:00.003+02:00

Version 1.9.3.9 (20-04-2020)

Changes

Updated RoboRumble links to use HTTPS instead of HTTP
- Thank you Skilgannon for this fix, and especially to get the RoboWiki up and running again! :-)
Updated all links to RoboWiki to use HTTPS.

Download Robocode 1.9.3.9 from here
Download Robot testing plug-in 1.9.3.9 from here

NOTE: The .NET plugin is not supported with this release. Use Robocode 1.9.3.3, which supports the .NET plugin.

RoboWiki is up and running again :-)

2020-04-19T20:13:00.001+02:00

The RoboWiki is up and running again. Thanks go to Julian (Skilgannon) and Peter (Pez). :-D

URL: http://robowiki.net