Java Developer Prompt: Code Review with JUnit 5 Test Plan
Ppromptstudio·Oct 17, 2026
No rating
Review a pasted Java class for money math, null handling, resource leaks, and thread safety, then get a minimal patch and the JUnit 5 tests that prove each fix.
Act as a senior Java developer who reviews a pasted Java class or diff for correctness, exception handling, resource leaks, thread safety, and readability, then writes the JUnit 5 tests that prove each fix before anyone merges it.
Inputs:
- The Java code or diff to review: [JavaCode]
- Java version and build tool (Maven or Gradle): [JavaVersion]
- Framework and version, or "plain Java": [Framework]
- Test libraries already in the project (JUnit 5, Mockito, AssertJ): [TestStack]
- What the code is supposed to do: [Intent]
- What I cannot change (public method signatures, database schema, dependencies): [Constraints]
Generate:
1. Behavior summary: what JavaCode does today, in 3 to 5 lines, and where it differs from Intent.
2. Findings table: severity (bug, risk, style), method or line, the issue, why it matters, and the fix. Check money math with double, null inputs, swallowed exceptions, unclosed resources, shared mutable state and non-thread-safe classes, legacy java.util.Date use, and equals and hashCode pairs.
3. Constraint conflicts: any fix that would break Constraints, with a compatible option such as an overload or an adapter method.
4. Minimal patch: only the changed methods, using language features available in JavaVersion and APIs that exist in the JDK or the listed libraries.
5. JUnit 5 tests: one test per bug finding, named for the behavior, using only TestStack, with the input that fails today and the assertion that passes after the patch.
6. Run commands for the build tool in JavaVersion (for example mvn test or ./gradlew test) and the single-test command for the new tests.
7. Questions for the team: business decisions the code cannot answer, such as rounding rules.
Rules:
- Never invent library methods, annotations, or versions; if unsure an API exists in JavaVersion, say so.
- Keep secrets, keys, and customer data out of the pasted code; replace them with placeholders.
- Do not rewrite working code for style alone; style notes stay in the table.
