coding-java

A set of Java coding standards covering names, imports, file structure, exceptions, concurrency, and quality rules for the ECHO Protocol. It gives examples such as PascalCase for classes and camelCase for methods and variables.

In plain words
What is it for?
Use it when writing or reviewing Java code to choose names, organize packages and imports, handle exceptions, manage concurrent work, and structure source files.
Why use it?
It helps keep Java code consistent and makes errors, dependencies, and shared-state behavior easier to understand. Clear rules also reduce disagreements during reviews and maintenance.

Skill for Claude CodeCodex

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 skills/savant0x/savant-code/coding-java
Any agent
npx skills add savant0x/savant-code --skill coding-java
Clone the repo
git clone --depth 1 https://github.com/savant0x/savant-code

Made for: Claude Code, Codex.

Per session 21 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 597 The whole file, excluding the scripts and references it only reads on demand.
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 $0.00021 $0.00597
Opus 5 $0.00010 $0.00298
Sonnet 5 $0.00004 $0.00119
Haiku 4.5 $0.00002 $0.00060

Measured 2d ago against content hash 01e5e441b17e, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

coding-java 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.

.agents/skills/coding-java/SKILL.md · 80 lines

How it starts

The opening of the file, as written. The whole thing — 80 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Java Coding Standards

Naming Conventions

Element Convention Example
Classes PascalCase UserProfile, GameState
Interfaces PascalCase Serializable, Renderable
Methods camelCase calculateDistance, spawnUnit
Variables camelCase playerCount, isValid
Constants UPPER_SNAKE_CASE MAX_PLAYERS, TILE_SIZE
Enums PascalCase (class), UPPER_SNAKE_CASE (values) TileType.GRASSLAND
Packages lowercase, reversed domain com.example.gameengine
Files PascalCase.java (match class name) UserProfile.java

Patterns

Error Handling

  • Use custom exception hierarchy extending Exception
  • Catch specific exceptions, never bare Exception
  • Use try-with-resources for AutoCloseable
  • Log at catch points with context

Concurrency

  • Prefer ExecutorService over raw threads
  • Use synchronized or ReentrantLock for shared state
  • Immutable objects preferred over synchronization
  • Use CompletableFuture for async composition

Imports

  • Group: java → javax → external → internal
  • No wildcard imports
  • Use IDE auto-import management

File Structure

src/main/java/com/example/
├── Application.java         # Entry point
├── config/
│   └── AppConfig.java       # Configuration
├── exception/
│   └── AppException.java    # Custom exceptions
├── model/
│   └── [Domain].java        # Data classes
├── service/
│   └── [Domain]Service.java # Business logic
src/test/java/
└── [Mirror structure]

Anti-Patterns to Flag

  • Bare catch (Exception e)
  • Mutable static fields
  • God classes (>300 lines)
  • Deep inheritance hierarchies (>3 levels)
  • null returns instead of Optional
  • Magic numbers (extract to constants)

Quality Overrides

These override the defaults in protocol.config.yaml when Java is the configured language.

Setting Default Java Override Reason
max_file_lines 300 350 Java boilerplate (imports, generics) adds lines
max_function_lines 50 40 Java methods should be shorter due to verbosity
max_line_length 100 120 Standard Java convention

Read the full file on GitHub · 80 lines

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 · 80 lines · 21 tokens per session scan A 01e5e441b17e

Subscribe to this mod's changes

coding-java is a skill published in the GitHub repository savant0x/savant-code (11 stars, last pushed 11d ago), licensed Apache-2.0. It adds 21 tokens to every session and 597 once invoked, about $0.0001 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 2026-08-30.

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