Robocode News

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.

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.

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.

Version 1.9.5.4 (30-Sep-2024)

Bugfix

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

Version 1.9.5.2 (24-Oct-2023)

Bugfix:

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

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.

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:

shell _JAVA_OPTIONS="-Djava.security.manager=allow"... read more

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! :)... read more

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. ... read more

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.

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

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! :)... read more

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.

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.... read more

Robocode 1.9.4.2 has been released

This version is a maintenance release that fixes issues with team robots. Read more about it here:
https://robo-code.blogspot.com/2021/05/robocode-1942.html

Happy TeamRobot coding! :)

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.... read more

The RoboWiki is currently down. Julian Kent is providing a temporary RoboWiki based on a backup from September running on a Raspberry Pi:
http://robowiki.duckdns.org

A big thanks go to Xor (@bumfo) for the recent fixes and improvements. 😃👍

https://robo-code.blogspot.com/2020/03/robocode-1938.html

This version fixes a problem where robot could not be found when compiled, and problems regarding development versions of robots (marked with a asterix character). Robots are also detected faster under RoboRumble. A security issue with DNS interaction has also been fixed.

https://robo-code.blogspot.com/2019/05/robocode-1936.html

Robocode 1.9.3.5 has just been released, which fixes issues for the RoboRumble and also adds support for developing robots in the Kotlin programming language.

Enjoy Robocoding! :-)

https://robo-code.blogspot.com/2019/03/robocode-1935.html

This release fixes issues with packaging robot teams, handles a visual HiDPI scaling issue, and running more frequent checks with the RoboRumble server.
Read more about it here:
http://robo-code.blogspot.dk/2018/03/robocode-1931.html

Robocode 1.8.1.0 has just been released, which is a maintenance release that fixes the Skipped Turns issues among other issues. :-)
Enjoy!
http://robo-code.blogspot.dk/2013/03/robocode-1810.html

Robocode 1.7.4.4 has been released Read the details here:
http://robo-http://robo-code.blogspot.dk/2012/11/robocode-1744.html

Robocode 1.7.4.3 has been released
Read the details here:
http://robo-code.blogspot.dk/2012/11/robocode-1743_17.html

Read the details here:
http://robo-code.blogspot.dk/2012/08/robocode-1742.html

Read more about it here:
http://robo-code.blogspot.com/2012/07/robocode-1741.html