How has backward compatibility strategies changed in recent Java versions?

Backward compatibility in Java has evolved significantly with recent versions. Traditionally, Java has strived to maintain backward compatibility, allowing older Java applications to run on newer Java versions without modification. However, as the language has developed, changes to strategies have emerged, particularly in response to new features, performance improvements, and security enhancements.

In recent versions, such as Java 9 and onwards, the introduction of the module system (Project Jigsaw) has added complexity. Although it aims to provide better encapsulation and performance, it can potentially break backward compatibility for applications that rely on internal APIs. Subsequent versions have continued to refine these systems, balancing between innovation and the need to maintain compatibility.

In addition, new language features like var handles, switch expressions, and text blocks have focused on improving developer experience while managing the risk of backward compatibility issues. The Java community continues refining the Java Language Specification (JLS) to ensure a smoother transition for developers upgrading their applications.

Overall, the approach to backward compatibility in Java has transitioned to accommodate new enhancements while minimizing disruption for legacy applications.