With the release of Xpress 9.8 (October 2025), the Xpress BCL (Builder Component Library for Java, .NET, and C++) has been deprecated. BCL libraries and documentation will continue to ship with Xpress distributions.
The new object-oriented APIs for Java and .NET (introduced in Xpress 9.4, April 2024) and C++ (Xpress 9.6, October 2024) provide a higher-performant alternative to BCL. These APIs are more tightly integrated with the low-level matrix-oriented interfaces and are designed to work naturally with modern software paradigms.
The new APIs offer
Recommendations for existing users
BCL users, particularly those working on iterative optimization algorithms, will see the most immediate benefit from migrating to the object-oriented API. Users of the matrix-oriented APIs are also encouraged to evaluate the new APIs for their workflows.
Any new users of Xpress APIs in Java, .NET, or C++ should adopt the new object-oriented APIs exclusively. To support existing users through this transition, migration guidance is available and can be found at the links below:
Existing users will encounter deprecation warnings at initialization, problem creation, and optimization. The BCL libraries remain bundled with the Xpress installer, and documentation is available locally in PDF and the API reference for Java and .NET are available HTML format following installation. BCL documentation is no longer included in the online documentation.
We recognize the investment our customers and partners have made in applications built on Xpress BCL. These changes are designed to protect that investment while giving users access to a modern, expressive, and highly capable API going forward.
The new object-oriented APIs for Java and .NET (introduced in Xpress 9.4, April 2024) and C++ (Xpress 9.6, October 2024) provide a higher-performant alternative to BCL. These APIs are more tightly integrated with the low-level matrix-oriented interfaces and are designed to work naturally with modern software paradigms.
The new APIs offer
- Full support for all solver features and modern language constructs
- A consistent development experience across Java, .NET, and C++
- Improved memory efficiency and runtime performance
- A single modeling object synchronized with the solver, minimizing memory overhead
- Model build times up to 8x faster for large-scale models with millions of variables and constraints
Recommendations for existing users
BCL users, particularly those working on iterative optimization algorithms, will see the most immediate benefit from migrating to the object-oriented API. Users of the matrix-oriented APIs are also encouraged to evaluate the new APIs for their workflows.
Any new users of Xpress APIs in Java, .NET, or C++ should adopt the new object-oriented APIs exclusively. To support existing users through this transition, migration guidance is available and can be found at the links below:
Existing users will encounter deprecation warnings at initialization, problem creation, and optimization. The BCL libraries remain bundled with the Xpress installer, and documentation is available locally in PDF and the API reference for Java and .NET are available HTML format following installation. BCL documentation is no longer included in the online documentation.
We recognize the investment our customers and partners have made in applications built on Xpress BCL. These changes are designed to protect that investment while giving users access to a modern, expressive, and highly capable API going forward.
Updated 6 months ago
Version 3.0