101-java-concurrency

A set of Java rules for writing code that safely handles concurrency, where multiple tasks run at the same time.

In plain words
What is it for?
Use it as guidance when adding or reviewing Java code that uses multiple threads or concurrent operations.
Why use it?
It reminds developers to choose thread-safe data structures, collections, classes, methods, objects, and variables when shared work can overlap.

Cursor rule for Cursor

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add rules/jabrena/jbang-mcp-examples/101-java-concurrency
Clone the repo
git clone --depth 1 https://github.com/jabrena/jbang-mcp-examples

Made for: Cursor.

Per session 102 This file is loaded in full into every session.
When invoked 102 The same file — it is already loaded in full.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00102 $0.00102
Opus 5 $0.00051 $0.00051
Sonnet 5 $0.00020 $0.00020
Haiku 4.5 $0.00010 $0.00010

Measured 2d ago against content hash 16681433b7b9, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

101-java-concurrency scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

.cursor/rules/101-java-concurrency.mdc · 18 lines

What it actually says

concurrency_guidelines:

  • Use thread-safe data structures
  • Use thread-safe collections
  • Use thread-safe classes
  • Use thread-safe methods
  • Use thread-safe objects
  • Use thread-safe variables
  • Use thread-safe methods
  • Use thread-safe objects
  • Use thread-safe variables
Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2d ago First seen · 18 lines · 102 tokens per session scan A 16681433b7b9

Subscribe to this mod's changes

101-java-concurrency is a cursor rule published in the GitHub repository jabrena/jbang-mcp-examples (1 stars, last pushed 1y ago), licensed Apache-2.0. It adds 102 tokens to every session, about $0.0005 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.