What&#s New in Java A Comprehensive Overview

Java Development Kit (JDK) 23 is on the horizon, with the release candidate now available and general availability scheduled for September 17, 2024. This release brings a variety of new features and enhancements that continue to evolve the Java programming language, though it's important to note that JDK 23 is a non-LTS (Long Term Support) release, offering only six months of support from Oracle. Here's a look at the most notable additions and changes in JDK 23.

Key Features and Enhancements

1. Scoped Values (Third Preview): Scoped values, introduced in previous versions, make it easier to share immutable data within threads and with child threads. This feature is particularly beneficial when used with virtual threads and structured concurrency, reducing the overhead associated with thread-local values. In JDK 23, the ScopedValue.callWhere method sees an update, introducing a new functional interface that simplifies exception handling, while the ScopeValue.getWhere method has been removed.

2. Structured Concurrency (Third Preview): Structured concurrency aims to simplify concurrent programming by treating related tasks across multiple threads as a single unit of work. This enhancement improves error handling and observability, reducing risks like thread leaks and cancellation delays. This is the third preview of structured concurrency, continuing to build on its earlier iterations.

3. Flexible Constructor Bodies (Second Preview): This feature, previously known as "statements before super(…)," allows constructors to initialize fields before invoking a superclass constructor. This change gives developers more freedom to structure constructor logic, streamlining the process of creating classes while maintaining the top-down execution order of constructors.

4. Implicitly Declared Classes and Instance Methods: Designed to make Java more accessible for beginners, this feature allows for simpler class declarations and easier expansion of programs. JDK 23 introduces additional enhancements, including the automatic import of three static methods for text I/O and all public top-level classes and interfaces of packages exported by the java.base module.

5. Module Import Declarations (Preview): This new feature allows entire modules to be imported with a single declaration, simplifying the use of modular libraries. It aims to make Java more user-friendly for beginners and reduce the clutter of multiple import statements when using various parts of a module's API.

6. Markdown Documentation Comments: JDK 23 introduces the ability to write JavaDoc comments using Markdown, making documentation more readable and easier to write. This change should streamline the process of creating and maintaining API documentation.

7. Z Garbage Collector (ZGC) in Generational Mode: The default mode for ZGC will now be generational, focusing on more frequent collection of young objects to boost application performance. The non-generational mode will be deprecated, signaling a shift towards a more modern approach in garbage collection.

8. Vector API (Eighth Incubation): Continuing its development, the Vector API enables developers to express vector computations that compile efficiently across different CPU architectures. This incubation aims to provide a reliable, performance-oriented API for vector processing.

9. Stream Gatherers (Second Preview): This enhancement to the Stream API introduces custom intermediate operations, making stream pipelines more flexible and capable of handling infinite streams.

10. Class-File API: A new API for processing class files is being introduced, aligning with the Java Virtual Machine specification. This API is set to replace the internal ASM library, providing a more standardized approach to class file processing.

11. Primitive Types in Patterns, instanceof, and switch (Preview): This feature enhances pattern matching by allowing primitive types in pattern contexts, extending instanceof and switch statements to work with all primitive types.

더 이상 사용되지 않는 기능 및 제거

• sun.misc.Unsafe의 메모리 액세스 방법: sun.misc.Unsafe의 메모리 액세스 방법은 JDK 23에서 더 이상 사용되지 않으며 향후 릴리스에서는 제거될 계획입니다. 개발자는 향후 Java 버전과의 호환성을 보장하기 위해 VarHandle API 또는 외부 함수 및 메모리 API로 전환하는 것이 좋습니다.

주목할만한 제외

• 문자열 템플릿: 원래 JDK 21 및 JDK 22에서 미리 보았던 문자열 템플릿이 JDK 23에서 제거되었습니다. 이 기능은 Java의 문자열 처리를 개선하기 위한 것이지만 추가 평가 및 잠재적인 재설계를 위해 연기되었습니다.

최종 생각

Java 23은 동시 프로그래밍 단순화, 성능 향상, 새로운 개발자가 Java에 더 쉽게 접근할 수 있도록 하는 데 중점을 두고 Java 플랫폼을 지속적으로 개선하고 향상합니다. LTS 릴리스는 아니지만 JDK 23에 도입된 기능은 Java의 향후 개발을 위한 발판을 마련하여 개발자 커뮤니티에 흥미로운 업데이트가 되었습니다. ??

Java 23은 현대 프로그래밍 방식의 선두에 머물고자 하는 개발자에게 필수적인 업데이트가 될 예정입니다. 숙련된 전문가이든 이제 막 Java를 시작하는 사람이든 관계없이 이러한 새로운 기능은 모든 사람에게 유용한 기능을 제공합니다.

시리즈 색인

The above is the detailed content of What&#s New in Java A Comprehensive Overview. For more information, please follow other related articles on the PHP Chinese website!