Java Clean Code

Workflow

1. Understand existing behavior, tests, and local style before editing.
2. Remove accidental complexity before adding abstractions.
3. Keep changes small, behavior-preserving, and easy to review.
4. Add tests only when refactor risk or missing coverage justifies it.

Principles

• KISS: choose straightforward control flow over clever composition.
• YAGNI: remove unused extension points, speculative interfaces, and future-only options.
• DRY: remove meaningful duplication; keep duplication when abstraction would hide important differences.
• Single responsibility: give each class/method one clear reason to change.
• Local consistency beats generic best-practice churn.
• Prefer guard clauses when they reduce nesting and expose the normal path.

Checks

• Names reveal domain meaning and avoid vague terms like

  data

  ,

  info

  ,

  manager

  , or

  helper

  when a precise name exists.
• Methods are short enough to scan and avoid mixed abstraction levels.
• Branching is simplified with guard clauses where it improves readability.
• Parameters are limited; related arguments become existing DTO/value types only when that matches project style.
• Boolean flags do not hide multiple behaviors in one method.
• Repeated validation, mapping, or query fragments are extracted only when the abstraction has a clear owner.
• Comments explain intent, constraints, or non-obvious tradeoffs; obvious narration is removed.
• Magic values become named constants when they carry domain meaning.
• Primitive obsession is replaced with domain value types only when validation or behavior repeats.
• Null handling is explicit and consistent with project conventions.
• Exceptions preserve context without swallowing causes.
• Refactors do not alter logs, metrics, transactions, or security behavior unintentionally.

Output