Java Code Review

This is a thorough Java code review checklist that catches the stuff that actually breaks production: null pointer exceptions, swallowed exceptions, concurrent modification errors, and resource leaks. It walks through eight categories from null safety to performance gotchas, showing bad versus good patterns with real code examples. The format is clean, listing findings by severity from critical to minor, and it reminds you to note good practices too. It's opinionated in the right ways, like preferring Optional over null returns and pushing back on overusing streams. If you're doing PR reviews or need a second set of eyes before merge, this gives you a systematic way to catch issues without relying purely on memory.

skills.sh installs: 1.1K
GitHub stars: 771
last updated: Aug 21, 2026

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Install

$ npx -y skills add decebals/claude-code-java --skill java-code-review --agent claude-code

Installs into .claude/skills of the current project.

Files

Java Code Review Skill

Systematic code review checklist for Java projects.

When to Use

User says "review this code" / "check this PR" / "code review"
Before merging a PR
After implementing a feature

Review Strategy

Quick scan - Understand intent, identify scope
Checklist pass - Go through each category below
Summary - List findings by severity (Critical → Minor)

Output Format

## Code Review: [file/feature name]

### Critical
- [Issue description + line reference + suggestion]

### Improvements
- [Suggestion + rationale]

### Minor/Style
- [Nitpicks, optional improvements]

### Good Practices Observed
- [Positive feedback - important for morale]

Review Checklist

1. Null Safety

Check for:

// ❌ NPE risk
String name = user.getName().toUpperCase();

// ✅ Safe
String name = Optional.ofNullable(user.getName())
    .map(String::toUpperCase)
    .orElse("");

// ✅ Also safe (early return)
if (user.getName() == null) {
    return "";
}
return user.getName().toUpperCase();

SKILL.md on GitHub