6.0.0 is available: choco-solver 🐙 moves to Java 17

[cprudhom]

6.0.0 - 05 May 2026

Major features:

Constraints & LCG

• Faster modulo constraints with bounded variables
• Fix modulo constraint with negative values
• Add lcgExtractFromVariablesOnSolution setting to control whether the solution-forbidding clause is built from variable assignments (true) or from the decision path (false, default)
• Add optimized implementations for the element constraint
• Improve filtering of signs of variables in PropDivXYZ
• Fix SparseBitSet.prevClearBit(final int fromIndex)

Build, CI & Tooling

• Migrate to Java 17 (<release>17</release>); Java 17 language features and APIs are now available
• Simplify Maven compiler configuration: remove multi-release JAR dual-compilation strategy (Java 8 + module-info at Java 9)
• Enforce minimum Java 17 and Maven 3.6.0 via maven-enforcer-plugin
• Upgrade ANTLR from 4.9.3 to 4.13.2; migrate grammars to standard src/main/antlr4/ layout; generated parser sources are no longer committed to the repository
• Upgrade TestNG from 7.5.1 to 7.12.0
• Upgrade args4j from 2.33 to 2.37

Deprecated API (to be removed in next release):

Other closed issues and pull requests:

See milestone 5.0.2

Contributors to this release:

• Charles Prud'homme (@cprudhom)
• Jean-Guillaume Fages (@jgFages)
• Arthur Godet (@ArthurGodet)