jetty-checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
  "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
  "https://checkstyle.org/dtds/configuration_1_3.dtd">

<!--
    Checkstyle configuration that checks the Jetty coding conventions.
 -->

<module name = "Checker">
  <property name="charset" value="UTF-8"/>

  <property name="severity" value="warning"/>

  <property name="fileExtensions" value="java"/>

  <!-- Excludes all 'module-info.java' files              -->
  <!-- See https://checkstyle.org/config_filefilters.html -->
  <module name="BeforeExecutionExclusionFileFilter">
    <property name="fileNamePattern" value="module\-info\.java$"/>
  </module>

  <!-- Checks for whitespace                               -->
  <!-- See http://checkstyle.sf.net/config_whitespace.html -->
  <module name="FileTabCharacter">
    <property name="eachLine" value="true"/>
  </module>

  <module name="TreeWalker">
    <module name="SuppressionCommentFilter">
      <property name="offCommentFormat" value="@checkstyle-disable-check : ([\w\|]+)"/>
      <property name="onCommentFormat" value="@checkstyle-enable-check : ([\w\|]+)"/>
      <property name="checkFormat" value="$1"/>
    </module>

    <!--
      Eclipse Jetty Specific.
      ===========================================================================================
      -->

    <!-- Location of Annotations -->
    <module name="AnnotationLocation">
      <property name="allowSamelineSingleParameterlessAnnotation" value="false"/>
    </module>

    <!-- Catch Parameter Name Format -->
    <module name="CatchParameterName">
      <property name="format" value="^(e|t|x|ex|th|e2|[a-z][a-z][a-zA-Z0-9]+)$"/>
    </module>

    <!-- Class Type Parameter Name Format -->
    <module name="ClassTypeParameterName">
      <property name="format" value="^[A-Z][A-Z0-9]*$"/>
    </module>

    <!-- Import Line Ordering -->
    <module name="CustomImportOrder">
      <property name="sortImportsInGroupAlphabetically" value="true"/>
      <property name="separateLineBetweenGroups" value="true"/>
      <property name="customImportOrderRules" value="STANDARD_JAVA_PACKAGE###THIRD_PARTY_PACKAGE###STATIC"/>
    </module>

    <!-- do not allow empty blocks in: try, finally, if, else, or switch -->
    <module name="EmptyBlock">
      <property name="option" value="TEXT"/>
      <property name="tokens"
                value="LITERAL_TRY, LITERAL_FINALLY, LITERAL_IF, LITERAL_ELSE, LITERAL_SWITCH"/>
    </module>

    <!-- enforce empty line after specified tokens  -->
    <module name="EmptyLineSeparator">
      <property name="allowNoEmptyLineBetweenFields" value="true"/>
      <property name="allowMultipleEmptyLines" value="false"/>
      <property name="tokens"
                value="PACKAGE_DEF, IMPORT, STATIC_IMPORT, CLASS_DEF, INTERFACE_DEF, ENUM_DEF,
                       STATIC_INIT, INSTANCE_INIT, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>
    </module>

    <!-- Indentation Rules -->
    <module name="Indentation">
      <property name="arrayInitIndent" value="8"/>
    </module>

    <!-- Interface Type Parameter Name -->
    <module name="InterfaceTypeParameterName">
      <property name="format" value="^[A-Z][A-Z0-9]*$"/>
    </module>

    <!-- left curly brace must be on new line -->
    <module name="LeftCurly">
      <property name="option" value="nl"/>
    </module>

    <!-- Method Type Parameter Name -->
    <module name="MethodTypeParameterName">
      <property name="format" value="^[A-Z][A-Z0-9]*$"/>
    </module>

    <!-- Member Name Format -->
    <module name="MemberName">
      <property name="format" value="^[_a-z][a-zA-Z0-9]*$" />
    </module>

    <!-- require braces is disabled - we don't enforce that in Jetty
    <module name="NeedBraces">
      <property name="allowSingleLineStatement" value="true"/>
    </module>
     -->

    <!-- Enforced Whitespace After specific tokens -->
    <module name="WhitespaceAfter">
      <property name="tokens" value="COMMA, SEMI, LITERAL_IF, LITERAL_ELSE, LITERAL_WHILE, LITERAL_DO, LITERAL_FOR, DO_WHILE" />
    </module>

    <!-- No Whitespace After specific tokens -->
    <module name="NoWhitespaceAfter">
      <property name="tokens" value="ARRAY_INIT, AT, INC, DEC, UNARY_MINUS, UNARY_PLUS, BNOT, LNOT, DOT, ARRAY_DECLARATOR, INDEX_OP, TYPECAST" />
      <property name="allowLineBreaks" value="true" />
    </module>

    <!-- No Whitespace Before specific tokens -->
    <module name="NoWhitespaceBefore">
      <property name="tokens"
                value="COMMA, SEMI, POST_INC, POST_DEC, DOT, ELLIPSIS, METHOD_REF"/>
      <property name="allowLineBreaks" value="true"/>
    </module>

    <!-- allowed wrapping for operators -->
    <module name="OperatorWrap">
      <property name="id" value="OperatorWrapNextLine"/>
      <property name="tokens" value="QUESTION, COLON"/>
      <property name="option" value="nl"/>
    </module>
    <module name="OperatorWrap">
      <property name="id" value="OperatorWrapSameLine"/>
      <property name="tokens" value="EQUAL, NOT_EQUAL, DIV, PLUS, MINUS, STAR, MOD, SR, BSR, GE, GT, SL, LE, LT, BXOR, BOR, LOR, BAND, LAND, TYPE_EXTENSION_AND, LITERAL_INSTANCEOF"/>
      <property name="option" value="eol"/>
    </module>

    <!-- ensure we don't have legacy comments that confuse javadoc tooling -->
    <module name="Regexp">
      <property name="id" value="LegacyMethodSeparators"/>
      <property name="format" value="/\*\s*[=*-]+\s*\*/" />
      <property name="illegalPattern" value="true"/>
      <property name="ignoreComments" value="false"/>
      <property name="message" value="Legacy Method Separators"/>
    </module>

    <!-- right curly brace must be on new line -->
    <module name="RightCurly">
      <property name="option" value="alone_or_singleline"/>
    </module>

    <!-- Various Wrapping of ".", ",", "...", "[]", and method ref New Lines -->
    <module name="SeparatorWrap">
      <property name="id" value="SeparatorWrapNextLine"/>
      <property name="tokens" value="DOT"/>
      <property name="option" value="nl"/>
    </module>
    <module name="SeparatorWrap">
      <property name="id" value="SeparatorWrapSameLine"/>
      <property name="tokens" value="COMMA, ELLIPSIS, ARRAY_DECLARATOR, METHOD_REF"/>
      <property name="option" value="eol"/>
    </module>

    <!-- checks that a token is followed by whitespace -->
    <module name="WhitespaceAround">
      <property name="allowEmptyConstructors" value="true"/>
      <property name="allowEmptyLambdas" value="true"/>
      <property name="allowEmptyMethods" value="true"/>
      <property name="allowEmptyTypes" value="true"/>
      <property name="allowEmptyLoops" value="true"/>
    </module>

    <!--
      Checks based on common Open Source specific recommendations.
      ===========================================================================================
      -->

    <!-- limit use of unicode escape sequences (eg "\u20ac") in mainline code. -->
    <module name="AvoidEscapedUnicodeCharacters">
      <!-- allow control characters to use unicode escape sequences -->
      <property name="allowEscapesForControlCharacters" value="true"/>
      <!-- allow unicode escape sequences if also followed by tail comments -->
      <property name="allowByTailComment" value="true"/>
      <!-- allow use of non-printable escape sequences -->
      <property name="allowNonPrintableEscapes" value="true"/>
    </module>

    <!-- not allowing star import lines -->
    <module name="AvoidStarImport"/>

    <!-- if you have an empty catch block, name the caught exception "ignored" -->
    <module name="EmptyCatchBlock">
      <property name="exceptionVariableName" value="ignored"/>
    </module>

    <!-- if a switch statement contains java code, but lacks fall through comment its an error -->
    <module name="FallThrough"/>

    <!-- reject unicode or octal values in mainline code -->
    <module name="IllegalTokenText">
      <property name="tokens" value="STRING_LITERAL, CHAR_LITERAL"/>
      <property name="format"
                value="\\u00(09|0(a|A)|0(c|C)|0(d|D)|22|27|5(C|c))|\\(0(10|11|12|14|15|42|47)|134)"/>
      <property name="message"
                value="Consider using special escape sequence instead of octal value or Unicode escaped value."/>
    </module>

    <!-- all switch statements should have "default" label declared -->
    <!-- Disabled: Is super noisy
    <module name="MissingSwitchDefault"/>
     -->

    <!-- prevent line wrapping of import / package statements -->
    <module name="NoLineWrap"/>

    <!-- only 1 top level class defined per java file -->
    <module name="OneTopLevelClass"/>

    <!-- Filename and Classname match -->
    <module name="OuterTypeFilename"/>

    <!--
       Checks based on the Java Language Specification recommendations.
       https://docs.oracle.com/javase/specs/jls/se8/html/index.html
      ===========================================================================================
      -->

    <!-- array type style -->
    <!-- int[] foo;  // OK
         int foo[];  // BAD -->
    <module name="ArrayTypeStyle" />

    <!-- Whitespace around Generics (angle brackets) follow convention -->
    <module name="GenericWhitespace" />

    <!-- Lambda Parameter Name Format -->
    <module name="LambdaParameterName" />

    <!-- Local Parameter Name Format -->
    <module name="LocalVariableName" />

    <!-- Method Name Format -->
    <module name="MethodName" />

    <!-- Checks the padding between the identifier of a method definition, constructor definition,
         method call, or constructor invocation: nospace -->
    <module name="MethodParamPad"/>

    <!-- ensure that modifiers follow suggested order -->
    <module name="ModifierOrder"/>

    <!-- only 1 variable declaration per line -->
    <module name="MultipleVariableDeclarations"/>

    <!-- No Object.finalize() use -->
    <module name="NoFinalizer"/>

    <!-- checks that there is only one statement per line -->
    <module name="OneStatementPerLine"/>

    <!-- package name JLS rules -->
    <module name="PackageName" />

    <!-- Parameter Name Format -->
    <module name="ParameterName" />

    <!-- the policy on the padding of parentheses: nospace -->
    <module name="ParenPad"/>

    <!-- Type Name format -->
    <module name="TypeName" />

    <!-- checks that long constants are defined with an upper ell. That is 'L' and not 'l' -->
    <module name="UpperEll"/>
    <!-- TODO: look for float / double version of above -->

  </module>
</module>