The OpenJDK’s plans for Java in 2025

Java enhancement plans for 2025 range from improving performance in the foreign function and memory (FFM) API, to working on ahead-of-time (AOT) code compilation, to finalizing the structured concurrency API, according to a recently published presentation from the OpenJDK community.

A January 16 video presentation by Oracle Java developer advocate Nicolai Parlog outlines the OpenJDK community’s ambitions for Java in 2025, based on Java enhancement projects Babylon, Leyden, Lilliput, Loom, Panama, and Valhalla. Another high-profile Java project, Project Amber, which develops smaller, productivity-oriented Java language features, will be the subject of second video in a week or so, Parlog said.

Project Babylon is aimed at extending Java to foreign programming models such as SQL, differentiable programming, machine learning models, and GPUs. Plans for Project Babylon in 2025 include preparing for the incubation of code reflection, as well as ongoing work on HAT (Heterogeneous Accelerator Toolkit), and exploring a prototype ONNX runtime script equivalent in Java. Goals for Project Leyden, which is aimed at improving the startup time of Java programs, include AOT method profiling and AOT code compilation.

Project Lilliput, meanwhile, will work to evaluate the impact of eight-byte object headers in the HotSpot JVM, with a “stretch goal” of four bytes. The overall objective is to free up 10% to 20% of the heap memory.

Project Loom is the OpenJDK project aimed at developing JVM features and APIs that support lightweight concurrency and new programming models. In 2025 Loom developers will work toward finalizing the structured concurrency API and the scoped values API. The team will also be working on pinning issues and improving lock information in thread dumps, Parlog said.

Project Panama, which works on improving the connections between the JVM and non-Java APIs, “has three objects in the fire,” Parlog said. These include a vector API, improving performance of the FFM API as well as record mappers for this API, and improvements to the jextract tool for generating Java bindings. And finally, Project Valhalla, which is aimed at augmenting the Java object model, will work toward a preview of value types, work on null-checked types, and do some early exploration of improved numerics and primitives.

All of these Java features in development will be worked on this year but they may not be released this year, Parlog warned. “Let’s be patient,” he said.