Code Style/Analysis Improvements

[AB-xdev]

Code Style/Analysis should be tighten in some places so that people who violate it get "roasted" by the CI running them.

[AB-xdev]

Rule inclusion criterica:

• Not a duplicate (Checkstyle/PMD)
• Rule is reasonable and not useless in 99.99% of time (e.g. no one uses Hastables anymore - as HashMaps exist since JDK 1.2)

Other criteria:

• to prevent extremely "braindead" code (like writing new String().getClass() instead of String.class)
• to prevent "Flüchtigkeitsfehler"

Planned changes:

• CheckStyle
  • AvoidDoubleBraceInitialization → Use Set.of(), List.of(), Arrays.asList()
  • IllegalCatch → Do not catch Error, Throwable and NPE, see PMD docs for details and explanation
  • UnnecessaryParentheses/Semicolon*
  • UnusedLocalVariable
  • (Removed) MissingSwitchDefault → Handed over to PMD
• PMD
  • AvoidPrintStackTrace → Use Logger
  • AvoidStringBufferField
  • ConstantsInInterface → Rule from Sonar
  • *Switch* → Needs to be handled by PMD as CheckStyle doesn't have a rule to differentiate enums and non enums (NonExhaustiveSwitch)
  • OneDeclarationPerLine
  • SimplifiableTestAssertion
  • SystemPrintln → Use a logger
  • Unused → Covers more cases then CheckStyle very low FP rate (1 FP method & 1 FP variable in 30k LoC)
  • UseEnumCollections
  • UseTryWithResources
  • LambdaCanBeMethodReference
  • UnnecessarySemicolon
  • AssignmentToNonFinalStatic
  • AvoidDecimalLiteralsInBigDecimalConstructor → Exteremly dangerous when working with prices
  • AvoidMultipleUnaryOperators
  • DontUseFloatTypeForLoopIndices
  • EqualsNull
  • IdempotentOperations
  • ImplicitSwitchFallThrough
  • InvalidLogMessageFormat → Mainly for people who don't know how the exception is handled
  • JumbledIncrementer
  • MoreThanOneLogger
  • NonStaticInitializer
  • ReturnFromFinallyBlock
  • SingletonClassReturningNewInstance
  • UnconditionalIfStatement
  • UselessOperationOnImmutable
  • UseUtilityClass → NOT handled by Checkstyle (Checkstyle only looks for the constructor)
  • PMD: Prevent usage of native HTML vaadin-addon-template#284 (Vaadin only)

Did not include the following PMD statements after consideration:

• GuardLogStatement - See [java] GuardLogStatement - Ignore getters and records pmd/pmd#5642
• LooseCoupling - Too many FP. Also usually not a hard problem - more like a warning/info

Further notes:

• synchronized... can be removed once Java 25 is here (and nothing runs on <24 anymore)

[AB-xdev]

Successfully applied to all active repos ✔