[OTHER] Enable more checks in checkstyle

[vil02]

What would you like to share?

#5110 introduced checkstyle. The config file has some of the rules commented out. It might a good idea to introduce some of them and discuss why the other ones are not needed in this repository.

List of checks which should be introduced

Few of the obvious checks, which should be introduced:

• ConstantName (style: enable ConstantName in checkstyle #5139 by @marysiuniq)
• LocalFinalVariableName (Enabled LocalFinalVariableName in Checkstyle #5172 by @CodaBlurd)
• LocalVariableName (style: enable LocalVariableName in CheckStyle #5191 by @cpu-pixel)
• MemberName (style: enable MemberName in checkstyle #5193 by @cpu-pixel)
• MethodName (style: enable MethodName in CheckStyle #5182 by @CodaBlurd)
• ParameterName (style: enable ParameterName in CheckStyle. #5196 by @CodaBlurd)
• StaticVariableName (style: enable StaticVariableName in checkstyle #5173 by @vaibhav9t1)
• TypeName (style: enable TypeName #5214 by @StarDxxx)
• AvoidStarImport (style: enable AvoidStarImport in checkstyle #5141)
• ModifierOrder (style: enable ModifierOrder in checkstyle #5132 by @marysiuniq)
• RedundantModifier (style: enable RedundantModifier in checkstyle #5140)
• EmptyStatement (style: enable EmptyStatement #5120)
• MultipleVariableDeclarations (style: enable MultipleVariableDeclarations in checkstyle #5175 by @vaibhav9t1)
• HideUtilityClassConstructor (style: enable HideUtilityClassConstructor in checkstyle #5147)
• ArrayTypeStyle (style: enable ArrayTypeStyle in checkstyle #5145)
• InvalidJavadocPosition (style: enable InvalidJavadocPosition in checkstyle #5237 by @samuelfac)
• OperatorWrap (style: enable OperatorWrap in checkstyle #5212 by @StarDxxx)
• ParenPad (style: enable ParenPad in checkstyle #5226 by @samuelfac)
• EqualsHashCode (style: enable EqualsHashCode in checkstyle #5157 by @CodaBlurd)
• InnerAssignment (style: enabled InnerAssignment in checkstyle #5162 by @CodaBlurd)
• FinalClass (style: enable FinalClass in checkstyle #5154 by @CodaBlurd)
• MissingSwitchDefault (style: enable MissingSwitchDefault in checkstyle #5179 by @BamaCharanChhandogi)
• NeedBraces (style: enable NeedBraces in checkstyle #5227 by @samuelfac)
• AvoidNestedBlocks (style: enable AvoidNestedBlocks in checkstyle #5228 by @samuelfac)
• WhitespaceAround (style: enable WhitespaceAround in checktyle #5241)
• TodoComment (style: enable TodoComment in checkstyle #5785 by @nishchalgv1)

(@siriak, @BamaCharanChhandogi feel free to edit the list above)

Additional information

How to contribute

1. select one check form the list above such that no one else is working on (and is not done yet),
2. write a comment "Hey, I am working on XYZ", where XYZ is your selected check,
3. in your fork, please create a branch like enable_XYZ,
4. uncomment the XYZ check in the checkstyle.xml,
5. run mvn checkstyle:check and fix all of the errors - please keep your changes minimal,
6. commit your changes with a message like "style: enable XYZ in checkstyle",
7. create a pull-request and mention this issue by writing something like "Related to [OTHER] Enable more checks in checkstyle #5119".

[vil02]

I will work on EmptyStatement.

[marysiuniq]

Hey, I will be working on ModifierOrder.

[marysiuniq]

Now, I will be working on ConstantName.

[vil02]

I will work on RedundantModifier.

[vil02]

I will slowly work on AvoidStarImport.

[VedSansare89]

Hey, I will be working on MethodName

[vil02]

I will work on ArrayTypeStyle.

[vil02]

I will work on HideUtilityClassConstructor.

[vil02]

@siriak, @BamaCharanChhandogi I have extended the list of obvious checks. Please have a look and edit the list if needed.

[CodaBlurd]

Hi, I will be working on FinalClass.

[CodaBlurd]

I will work on EqualsHashCode.

[CodaBlurd]

I will work on InnerAssignment.

[StarDxxx]

I will work on .OperatorWrap

[StarDxxx]

I will work on .TypeName.

[samuelfac]

I will work on ParenPad.

[samuelfac]

I will work on NeedBraces

[samuelfac]

I will work on AvoidNestedBlocks

[samuelfac]

I will work on InvalidJavadocPosition

[samuelfac]

WhitespaceAround it conflicts with clang-format. When I create the spaces clang-format undoes it and causes an error in the checkstyle.

[vil02]

WhitespaceAround it conflicts with clang-format. When I create the spaces clang-format undoes it and causes an error in the checkstyle.

Please have a look at #5241.

But you are right: some of the checks (like GenericWhitespace, NoWhitespaceAfter) conflict the current clang-format config.

[FishmmansCavalcante]

I will work on enabling the TodoComment check in the checkstyle.xml file.

[adityasarfare]

Hey Can I work on something ?

[siriak]

@adityasarfare sure, see what checks are disabled with todo and feel free to enable them one-by-one https://github.com/TheAlgorithms/Java/blob/master/checkstyle.xml

[vrp0211]

Hey, I am working on NoWhitespaceAfter

[vrp0211]

Hey, I am working on NoWhitespaceAfter

Looks like NoWhitespaceAfter is conflicting with clang-format missed the earlier comment , closing the PR

[Brijeshthummar02]

Hey, I am working on TodoComment.

[tanishkagupta27]

Hey, I am working on TodoComment.

[shamsulalam1114]

Hey, I am working on MissingSwitchDefault

[hrishi0902]

Hey, I am working on WhitespaceAround

[ananyadhagat]

Hey, I am working on TodoComment

[nishchalgv1]

Hey, I am working on TodoComment

[vil02]

@BamaCharanChhandogi, @CodaBlurd, @StarDxxx, @cpu-pixel, @marysiuniq, @nishchalgv1, @samuelfac, @vaibhav9t1: we did it! We not only improved the quality of the existing code, but also of all of the future code. Thanks for the effort!

@siriak, @BamaCharanChhandogi, @alxkm: I will close this issue as done, since the remaindering checks require some more discussion.