Java 22 Debuts: Scoped Values, Structured Concurrency, Stream Gatherers, and Multi-File Program Execution
Java Development Kit (JDK) 22 has officially arrived, introducing a range of new features and enhancements designed to boost productivity and streamline development. As a short-term release, JDK 22 will benefit from Premier support from Oracle for six months, providing developers with timely updates and fixes. Unlike long-term support releases, such as JDK 21, which will receive five years of Premier support and extended support until September 2031, JDK 22 is geared towards users seeking the latest advancements in Java with a shorter support cycle.
One of the notable updates in JDK 22 is the introduction of scoped values, a feature developed under Project Loom. Scoped values offer a new way to manage immutable data across threads, addressing the limitations of thread-local variables. By allowing efficient sharing of data within and across threads, scoped values aim to enhance both performance and ease of use. This addition is expected to simplify concurrency management and improve code clarity, especially in applications that require extensive threading.
Another significant feature in this release is the preview of stream gatherers. This enhancement to the Stream API allows developers to define custom intermediate operations for stream pipelines, enabling more flexible data transformations. Stream gatherers are designed to fill gaps left by existing built-in operations, offering greater control and customization for data processing tasks. This feature is part of the ongoing evolution of the Stream API, which continues to be a critical component of Java’s functional programming capabilities.
In addition to these features, JDK 22 includes a second preview of structured concurrency. Structured concurrency aims to simplify multi-threaded programming by introducing a more organized approach to handling concurrent tasks. This preview builds on previous iterations, refining the model and providing developers with better tools for managing complex concurrency scenarios. Alongside structured concurrency, other notable previews and incubations in this release include enhancements to the Java launcher, which now supports running multi-file programs, and a class-file API.
JDK 22 also advances several existing projects and proposals. This release continues to develop features from OpenJDK’s Amber, Loom, and Panama projects. Amber focuses on productivity-oriented language features, Loom enhances the Java virtual machine with new concurrency tools, and Panama facilitates interoperation between Java and non-Java APIs. These projects collectively contribute to the modernization of Java, addressing a variety of use cases and improving overall developer experience.
Other improvements in JDK 22 include a second preview of string templates, which offer a new way to work with text and formatting in Java. The release also introduces unnamed variables and patterns, a foreign function and memory API, and further advancements in the vector API, which is now in its seventh incubation. These updates reflect ongoing efforts to enhance Java’s versatility and performance, keeping the language relevant and competitive in an evolving software landscape.
Overall, JDK 22 represents a significant step forward in the evolution of Java, bringing a mix of new features and enhancements that cater to various aspects of development. While it is a short-term release, it sets the stage for future improvements and offers developers a chance to leverage the latest innovations in the Java ecosystem.