java-21

Implement Java 21 records, sealed types, and virtual threads.

Updated Mar 8, 2026
One-click install
npx skills add https://github.com/brivaro/brivaro-ai-wizard --skill java-21-brivaro
Or copy as Structured Prompt for Agent
Please help me install this Agent Skill.
Skill: java-21
Source: https://github.com/brivaro/brivaro-ai-wizard/tree/main/skills/java-21
Command: npx skills add https://github.com/brivaro/brivaro-ai-wizard --skill java-21-brivaro

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes references (resource) components.

What problem does it solve?

This Skill helps developers write modern, safe, and efficient Java 21 code by leveraging new language features and runtime capabilities.

Core Features & Use Cases

  • Immutable Data Structures: Utilize records for concise and safe data representation.
  • Exhaustive Pattern Matching: Employ sealed types with switch expressions for robust conditional logic.
  • Efficient Concurrency: Leverage virtual threads for scalable I/O-bound operations.
  • Use Case: When refactoring legacy Java code to adopt modern patterns for improved maintainability and performance.

Quick Start

Apply the java-21 skill to refactor the provided mutable DTO into a Java record.

Frequently Asked Questions about java-21

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I refactor a mutable DTO into a Java record for immutable data?

To refactor a mutable DTO into a Java record, replace traditional class boilerplate with the record keyword to achieve immutable data representation, ensuring safer and more maintainable Java 21 code structures.

What is the best way to use sealed types with pattern matching in Java 21?

Sealed types combined with pattern matching in switch expressions provide exhaustive conditional logic, allowing the compiler to enforce that all possible subtypes are handled safely and robustly.

How do virtual threads improve concurrency for blocking I/O operations in Java?

Virtual threads improve concurrency by enabling highly scalable handling of blocking I/O operations, allowing Java 21 applications to process massive concurrent workloads efficiently without exhausting platform threads.

When should I use Java 21 features to modernize my legacy codebase?

You should modernize legacy Java code when you need improved maintainability and performance, specifically by adopting records for immutable data and virtual threads for efficient I/O-bound concurrency.