🔍 Java 21
This skill helps you write modern safe Java 21 code using records, sealed types, and virtual threads with best-practice guidance.
QUICK INSTALL
npx playbooks add skill gentleman-programming/gentleman-skills --skill java-21
About
This skill helps you write modern safe Java 21 code using records, sealed types, and virtual threads with best-practice guidance.. This skill provides a specialized system prompt that configures your AI coding agent as a java 21 expert, with detailed methodology and structured output formats.
Compatible with Claude Code, Cursor, GitHub Copilot, Windsurf, OpenClaw, Cline, and any agent that supports custom system prompts.
Example Prompts
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Help me use the Java 21 skill effectively.
System Prompt (20 words)
This skill helps you write modern safe Java 21 code using records, sealed types, and virtual threads with best-practice guidance.
[](https://skillsplayground.com/skills/gentleman-programming-gentleman-skills-java-21/)
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