codestyle

name	codestyle
description	Project coding standards and conventions for Java 17 with Lombok, spring-javaformat, checkstyle, and PMD
user-invocable	false

Coding Standards

Formatting

• Indentation: Tabs (enforced by spring-javaformat 0.0.47)
• Formatter: io.spring.javaformat:spring-javaformat-maven-plugin — run spring-javaformat:apply before committing
• Checkstyle: Uses io.spring.javaformat.checkstyle.SpringChecks with custom suppressions
• PMD: Custom ruleset at pmd-ruleset.xml

Spring-javaformat Rules (enforced)

• Braces required: All if, else, for, while, do must use {} even for single-line bodies
• Lambda parentheses: Single-parameter lambdas must have parentheses: (x) -> not x ->
• Lambda blocks: Use expression body when possible: (x) -> x.toString() not (x) -> { return x.toString(); }
• Catch variables: Use ex not single-letter e: catch (Exception ex)
• Ternary parentheses: Wrap ternary conditions: (a != null) ? a : b not a != null ? a : b
• No star imports: Use explicit imports, never import java.util.*
• Newline at EOF: Files must end with a newline

Checkstyle Suppressions (in checkstyle-suppressions.xml)

These checks are suppressed project-wide:

• SpringHeaderCheck — no license header requirement
• JavadocPackage, JavadocType, JavadocMethod, JavadocVariable — Javadoc not enforced
• MissingJavadocType, MissingJavadocMethod — Javadoc not enforced
• SpringJavadoc — Javadoc description casing not enforced
• RegexpSinglelineJava — no regex line restrictions
• SpringImportOrder — import ordering not enforced
• RequireThis — this. prefix not required
• SpringTestFileName — test file naming flexible

PMD Exclusions (in pmd-ruleset.xml)

Key exclusions — these patterns are acceptable in this project:

Best Practices: GuardLogStatement, LiteralsFirstInComparisons, UnusedAssignment, DoubleBraceInitialization, NonExhaustiveSwitch, RedundantFieldInitializer

Code Style: LocalVariableNamingConventions, PrematureDeclaration, ConfusingTernary, UseLocaleWithCaseConversions, UseExplicitTypes, FieldNamingConventions

Design: CognitiveComplexity, NcssCount, SimplifyConditional, CollapsibleIfStatements, GodClass, DataClass, TooManyFields

Error Prone: ReturnEmptyCollectionRatherThanNull, AvoidDuplicateLiterals, NullAssignment

Naming

• Classes: PascalCase
• Methods/variables: camelCase
• Constants: UPPER_SNAKE_CASE

Lombok

• @Getter/@Setter for fields
• @Data for POJOs/DTOs
• @Builder with .toBuilder() for immutable construction
• @Slf4j for logging
• @NoArgsConstructor, @AllArgsConstructor as needed

Jackson 3

• Imports use tools.jackson.* namespace (not com.fasterxml.jackson)
• Exception: com.fasterxml.jackson.annotation.* annotations still use old namespace
• Jackson 3's readValue() no longer throws checked IOException

Dependencies

• Manage versions in root pom.xml <properties>
• Spring Boot parent manages most versions
• Only the starter module has real source code and code quality plugins

Testing

• JUnit 5 with Assertions
• Use @ParameterizedTest to avoid code duplication
• Test config classes in org.alexmond.sample.test.config
• JaCoCo enforces 80% minimum line coverage

Running code quality checks

# Format all code
bash "/path/to/mvn" io.spring.javaformat:spring-javaformat-maven-plugin:apply -f pom.xml -Pdefault -q

# Validate (checkstyle + PMD)
bash "/path/to/mvn" validate -f pom.xml -pl spring-boot-config-json-schema-starter

# Full build with tests
bash "/path/to/mvn" clean install -f pom.xml -Pdefault