checkstyle.xml

<?xml version="1.0" encoding="UTF-8"?>

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  http://www.apache.org/licenses/LICENSE-2.0

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specific language governing permissions and limitations
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<!DOCTYPE module PUBLIC
        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
        "https://checkstyle.org/dtds/configuration_1_3.dtd">

<module name="Checker">

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

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

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

    <module name="SuppressWarningsFilter"/>

    <!-- https://checkstyle.org/filters/suppressionfilter.html -->
    <module name="SuppressionFilter">
        <property name="file" value="${org.checkstyle.google.suppressionfilter.config}"
                  default="checkstyle-suppressions.xml" />
        <property name="optional" value="true"/>
    </module>

    <!-- https://checkstyle.org/filters/suppresswithnearbytextfilter.html -->
    <module name="SuppressWithNearbyTextFilter">
        <property name="nearbyTextPattern"
                  value="CHECKSTYLE.SUPPRESS\: (\w+) for ([+-]\d+) lines"/>
        <property name="checkPattern" value="$1"/>
        <property name="lineRange" value="$2"/>
    </module>

    <!-- Checks for whitespace                               -->
    <!-- See http://checkstyle.org/checks/whitespace/index.html -->
    <module name="FileTabCharacter">
        <property name="eachLine" value="true"/>
    </module>

    <module name="LineLength">
        <property name="fileExtensions" value="java"/>
        <property name="max" value="100"/>
        <property name="ignorePattern"
                  value="^package.*|^import.*|href\s*=\s*&quot;[^&quot;]*&quot;|http://|https://|ftp://"/>
        <property name="severity" value="warning"/>
    </module>
    <!--  Suppression to prevent LineLength Check from flagging lines in Text-blocks -->
    <module name="SuppressWithPlainTextCommentFilter">
        <property name="checkFormat" value="LineLength"/>
        <property name="offCommentFormat" value='^.*"""\s*$'/>
        <property name="onCommentFormat" value='^\s*"""\s*(?:[,;]|.+)$'/>
    </module>
    <module name="TreeWalker">
        <module name="OuterTypeFilename"/>
        <module name="MatchXpath">
            <property name="id" value="singleLineCommentStartWithSpace"/>
            <property name="query"
                      value="//SINGLE_LINE_COMMENT[./COMMENT_CONTENT[not(starts-with(@text, ' '))
                       and not(starts-with(@text, '/'))
                       and not(@text = '\n') and not(ends-with(@text, '//\n'))]]"/>
            <message key="matchxpath.match" value="''//'' must be followed by a whitespace."/>
        </module>
        <module name="IllegalTokenText">
            <property name="tokens" value="STRING_LITERAL, CHAR_LITERAL, TEXT_BLOCK_CONTENT"/>
            <property name="format"
                      value="\\u00(09|0(a|A)|0(b|B)|(0|1)(c|C)|(0|1)(d|D)|1(d|D)|1(e|E)|1(f|F)|22|27|5(C|c))|\\u1680|\\u3000|\\u20(00|0(a|A)|28|29|(2|5)(f|F))|\\(0(10|11|12|14|15|40|42|47)|134)"/>
            <property name="message"
                      value="Consider using special escape sequence instead of octal value or Unicode escaped value."/>
        </module>
        <module name="AvoidEscapedUnicodeCharacters">
            <property name="allowEscapesForControlCharacters" value="true"/>
            <property name="allowByTailComment" value="true"/>
            <property name="allowNonPrintableEscapes" value="true"/>
        </module>
        <module name="AvoidStarImport"/>
        <module name="OneTopLevelClass" />
        <module name="NoLineWrap">
            <property name="tokens" value="PACKAGE_DEF, IMPORT, STATIC_IMPORT"/>
        </module>
        <module name="NeedBraces">
            <property name="tokens"
                      value="LITERAL_DO, LITERAL_ELSE, LITERAL_FOR, LITERAL_IF, LITERAL_WHILE"/>
        </module>
        <module name="LeftCurly">
            <property name="id" value="LeftCurlyEol"/>
            <property name="tokens"
                      value="ANNOTATION_DEF, CLASS_DEF, CTOR_DEF, ENUM_CONSTANT_DEF, ENUM_DEF,
                    INTERFACE_DEF, LAMBDA, LITERAL_CATCH,
                    LITERAL_DO, LITERAL_ELSE, LITERAL_FINALLY, LITERAL_FOR, LITERAL_IF,
                    LITERAL_SWITCH, LITERAL_SYNCHRONIZED, LITERAL_TRY, LITERAL_WHILE, METHOD_DEF,
                    OBJBLOCK, STATIC_INIT, RECORD_DEF, COMPACT_CTOR_DEF"/>
        </module>
        <module name="LeftCurly">
            <property name="id" value="LeftCurlyNl"/>
            <property name="option" value="nl"/>
            <property name="tokens"
                      value="LITERAL_CASE, LITERAL_DEFAULT"/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <!-- LITERAL_CASE, LITERAL_DEFAULT are reused in SWITCH_RULE  -->
            <property name="id" value="LeftCurlyNl"/>
            <property name="query" value="//SWITCH_RULE/SLIST"/>
        </module>
        <module name="RightCurly">
            <property name="id" value="RightCurlySame"/>
            <property name="tokens"
                      value="LITERAL_TRY, LITERAL_CATCH, LITERAL_IF, LITERAL_ELSE,
                    LITERAL_DO"/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <property name="id" value="RightCurlySame"/>
            <property name="query" value="//RCURLY[parent::SLIST[parent::LITERAL_CATCH
                               and not(parent::LITERAL_CATCH/following-sibling::*)]]"/>
        </module>
        <module name="RightCurly">
            <property name="id" value="RightCurlyAlone"/>
            <property name="option" value="alone"/>
            <property name="tokens"
                      value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT,
                    INSTANCE_INIT, ANNOTATION_DEF, ENUM_DEF, INTERFACE_DEF, RECORD_DEF,
                    COMPACT_CTOR_DEF, LITERAL_SWITCH, LITERAL_CASE, LITERAL_FINALLY,
                    LITERAL_CATCH"/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <!-- suppression is required till https://github.com/checkstyle/checkstyle/issues/7541 -->
            <property name="id" value="RightCurlyAlone"/>
            <property name="query" value="//RCURLY[parent::SLIST[count(./*)=1
                               and not(parent::LITERAL_CATCH)]
                               or (preceding-sibling::*[last()][self::LCURLY]
                               and not(parent::SLIST/parent::LITERAL_CATCH))
                               or (parent::SLIST/parent::LITERAL_CATCH
                               and parent::SLIST/parent::LITERAL_CATCH/following-sibling::*)]"/>
        </module>
        <module name="WhitespaceAfter">
            <property name="tokens"
                      value="COMMA, SEMI, TYPECAST, LITERAL_IF, LITERAL_ELSE, LITERAL_RETURN,
                    LITERAL_WHILE, LITERAL_DO, LITERAL_FOR, LITERAL_FINALLY, DO_WHILE, ELLIPSIS,
                    LITERAL_SWITCH, LITERAL_SYNCHRONIZED, LITERAL_TRY, LITERAL_CATCH, LAMBDA,
                    LITERAL_YIELD, LITERAL_CASE, LITERAL_WHEN, ANNOTATIONS"/>
        </module>
        <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"/>
            <property name="allowEmptySwitchBlockStatements" value="true"/>
            <property name="ignoreEnhancedForColon" value="false"/>
            <property name="tokens"
                      value="ASSIGN, BAND, BAND_ASSIGN, BOR, BOR_ASSIGN, BSR, BSR_ASSIGN, BXOR,
                    BXOR_ASSIGN, COLON, DIV, DIV_ASSIGN, DO_WHILE, EQUAL, GE, GT, LAMBDA, LAND,
                    LCURLY, LE, LITERAL_CATCH, LITERAL_DO, LITERAL_ELSE, LITERAL_FINALLY,
                    LITERAL_FOR, LITERAL_IF, LITERAL_RETURN, LITERAL_SWITCH, LITERAL_SYNCHRONIZED,
                    LITERAL_TRY, LITERAL_WHILE, LOR, LT, MINUS, MINUS_ASSIGN, MOD, MOD_ASSIGN,
                    NOT_EQUAL, PLUS, PLUS_ASSIGN, QUESTION, RCURLY, SL, SLIST, SL_ASSIGN, SR,
                    SR_ASSIGN, STAR, STAR_ASSIGN, LITERAL_ASSERT,
                    TYPE_EXTENSION_AND, LITERAL_WHEN"/>
            <message key="ws.notFollowed"
                     value="WhitespaceAround: ''{0}'' is not followed by whitespace. Empty blocks
               may only be represented as '{}' when not part of a multi-block statement (4.1.3)"/>
            <message key="ws.notPreceded"
                     value="WhitespaceAround: ''{0}'' is not preceded with whitespace."/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <property name="checks" value="WhitespaceAround"/>
            <property name="query" value="//*[self::LITERAL_IF or self::LITERAL_ELSE or
                                 self::STATIC_INIT]/SLIST[count(./*)=1]
                                 | //*[self::STATIC_INIT or self::LITERAL_TRY or self::LITERAL_IF]
                                 //*[self::RCURLY][parent::SLIST[count(./*)=1]]
                                 | //SLIST[count(./*)=1][parent::LITERAL_TRY and
                                 not(following-sibling::*)]
                                 | //SLIST[count(./*)=1][parent::LITERAL_CATCH and
                                 not(parent::LITERAL_CATCH/following-sibling::*)]"/>
        </module>
        <module name="RegexpSinglelineJava">
            <property name="format" value="\{[ ]+\}"/>
            <property name="message" value="Empty blocks should have no spaces. Empty blocks
                                   may only be represented as '{}' when not part of a
                                   multi-block statement (4.1.3)"/>
        </module>
        <module name="OneStatementPerLine"/>
        <module name="MultipleVariableDeclarations"/>
        <module name="ArrayTypeStyle"/>
        <module name="JavadocLeadingAsteriskAlign"/>
        <module name="MissingSwitchDefault"/>
        <module name="FallThrough"/>
        <module name="UpperEll"/>
        <module name="ModifierOrder"/>
        <module name="EmptyLineSeparator">
            <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, RECORD_DEF,
                    COMPACT_CTOR_DEF"/>
            <property name="allowNoEmptyLineBetweenFields" value="true"/>
        </module>
        <module name="SeparatorWrap">
            <property name="id" value="SeparatorWrapDot"/>
            <property name="tokens" value="DOT"/>
            <property name="option" value="nl"/>
        </module>
        <module name="SeparatorWrap">
            <property name="id" value="SeparatorWrapComma"/>
            <property name="tokens" value="COMMA"/>
            <property name="option" value="EOL"/>
        </module>
        <module name="SeparatorWrap">
            <!-- ELLIPSIS is EOL until https://github.com/google/styleguide/issues/259 -->
            <property name="id" value="SeparatorWrapEllipsis"/>
            <property name="tokens" value="ELLIPSIS"/>
            <property name="option" value="EOL"/>
        </module>
        <module name="SeparatorWrap">
            <!-- ARRAY_DECLARATOR is EOL until https://github.com/google/styleguide/issues/258 -->
            <property name="id" value="SeparatorWrapArrayDeclarator"/>
            <property name="tokens" value="ARRAY_DECLARATOR"/>
            <property name="option" value="EOL"/>
        </module>
        <module name="SeparatorWrap">
            <property name="id" value="SeparatorWrapMethodRef"/>
            <property name="tokens" value="METHOD_REF"/>
            <property name="option" value="nl"/>
        </module>
        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
            <message key="name.invalidPattern"
                     value="Package name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="TypeName">
            <property name="format" value="^[A-Z][a-zA-Z0-9]*(?:[0-9](?:_[0-9]+)*)?$"/>
            <property name="tokens" value="CLASS_DEF"/>
            <message key="name.invalidPattern"
                     value="Type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="TypeName">
            <property name="tokens" value="INTERFACE_DEF, ENUM_DEF,
                    ANNOTATION_DEF, RECORD_DEF"/>
            <message key="name.invalidPattern"
                     value="Type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="MemberName">
            <property name="format"
                      value="^(?![a-z]$)(?![a-z][A-Z])[a-z][a-zA-Z0-9]*(?:_[0-9]+)*$"/>
            <message key="name.invalidPattern"
                     value="Member name ''{0}'' must match pattern ''{1}''."/>
            <property name="severity" value="warning"/>
        </module>
        <module name="ParameterName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Parameter name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="LambdaParameterName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Lambda parameter name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="CatchParameterName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Catch parameter name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="LocalVariableName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Local variable name ''{0}'' must match pattern ''{1}''."/>
            <property name="severity" value="warning"/>
        </module>
        <module name="PatternVariableName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Pattern variable name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="ClassTypeParameterName">
            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
            <message key="name.invalidPattern"
                     value="Class type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="RecordComponentName">
            <property name="format" value="^[a-z]([a-z0-9][a-zA-Z0-9]*)?$"/>
            <message key="name.invalidPattern"
                     value="Record component name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="RecordTypeParameterName">
            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
            <message key="name.invalidPattern"
                     value="Record type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="MethodTypeParameterName">
            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
            <message key="name.invalidPattern"
                     value="Method type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="InterfaceTypeParameterName">
            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)"/>
            <message key="name.invalidPattern"
                     value="Interface type name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="NoFinalizer"/>
        <module name="GenericWhitespace">
            <message key="ws.followed"
                     value="GenericWhitespace ''{0}'' is followed by whitespace."/>
            <message key="ws.preceded"
                     value="GenericWhitespace ''{0}'' is preceded with whitespace."/>
            <message key="ws.illegalFollow"
                     value="GenericWhitespace ''{0}'' should followed by whitespace."/>
            <message key="ws.notPreceded"
                     value="GenericWhitespace ''{0}'' is not preceded with whitespace."/>
        </module>
        <module name="Indentation">
            <property name="basicOffset" value="4"/>
            <property name="braceAdjustment" value="0"/>
            <property name="caseIndent" value="4"/>
            <property name="throwsIndent" value="4"/>
            <property name="lineWrappingIndentation" value="4"/>
            <property name="arrayInitIndent" value="4"/>
        </module>

        <module name="AbbreviationAsWordInName">
            <property name="ignoreFinal" value="false"/>
            <property name="allowedAbbreviationLength" value="0"/>
            <property name="tokens"
                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, ANNOTATION_DEF, ANNOTATION_FIELD_DEF,
                    PARAMETER_DEF, VARIABLE_DEF, METHOD_DEF, PATTERN_VARIABLE_DEF, RECORD_DEF,
                    RECORD_COMPONENT_DEF"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="NoWhitespaceBeforeCaseDefaultColon"/>
        <module name="OverloadMethodsDeclarationOrder"/>
        <module name="ConstructorsDeclarationGrouping"/>
        <module name="VariableDeclarationUsageDistance">
            <property name="severity" value="warning"/>
        </module>
        <module name="CustomImportOrder">
            <property name="sortImportsInGroupAlphabetically" value="true"/>
            <property name="separateLineBetweenGroups" value="true"/>
            <property name="customImportOrderRules" value="STATIC###THIRD_PARTY_PACKAGE"/>
            <property name="tokens" value="IMPORT, STATIC_IMPORT, PACKAGE_DEF"/>
        </module>
        <module name="MethodParamPad">
            <property name="tokens"
                      value="CTOR_DEF, LITERAL_NEW, METHOD_CALL, METHOD_DEF, CTOR_CALL,
                    SUPER_CTOR_CALL, ENUM_CONSTANT_DEF, RECORD_DEF, RECORD_PATTERN_DEF"/>
        </module>
        <module name="NoWhitespaceBefore">
            <property name="tokens"
                      value="COMMA, SEMI, POST_INC, POST_DEC, DOT,
                    LABELED_STAT, METHOD_REF, ELLIPSIS"/>
            <property name="allowLineBreaks" value="true"/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <property name="checks" value="NoWhitespaceBefore"/>
            <property name="query"
                      value="//ELLIPSIS[preceding-sibling::TYPE/ANNOTATIONS[ANNOTATION[LPAREN]
              or not(following-sibling::*)]]"/>
        </module>
        <module name="ParenPad">
            <property name="tokens"
                      value="ANNOTATION, ANNOTATION_FIELD_DEF, CTOR_CALL, CTOR_DEF, DOT, ENUM_CONSTANT_DEF,
                    EXPR, LITERAL_CATCH, LITERAL_DO, LITERAL_FOR, LITERAL_IF, LITERAL_NEW,
                    LITERAL_SWITCH, LITERAL_SYNCHRONIZED, LITERAL_WHILE, METHOD_CALL,
                    METHOD_DEF, QUESTION, RESOURCE_SPECIFICATION, SUPER_CTOR_CALL, LAMBDA,
                    RECORD_DEF, RECORD_PATTERN_DEF"/>
        </module>
        <module name="OperatorWrap">
            <property name="option" value="NL"/>
            <property name="tokens"
                      value="BAND, BOR, BSR, BXOR, DIV, EQUAL, GE, GT, LAND, LE, LITERAL_INSTANCEOF, LOR,
                    LT, MINUS, MOD, NOT_EQUAL, PLUS, QUESTION, SL, SR, STAR, METHOD_REF,
                    TYPE_EXTENSION_AND "/>
        </module>
        <module name="AnnotationLocation">
            <property name="id" value="AnnotationLocationMostCases"/>
            <property name="tokens"
                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF,
                      RECORD_DEF, COMPACT_CTOR_DEF, PACKAGE_DEF"/>
        </module>
        <module name="AnnotationLocation">
            <property name="id" value="AnnotationLocationVariables"/>
            <property name="tokens" value="VARIABLE_DEF"/>
            <property name="allowSamelineMultipleAnnotations" value="true"/>
        </module>
        <module name="NonEmptyAtclauseDescription">
            <property name="severity" value="warning"/>
        </module>
        <module name="InvalidJavadocPosition" />
        <module name="JavadocTagContinuationIndentation">
            <property name="severity" value="warning"/>
        </module>
        <module name="SummaryJavadoc">
            <property name="forbiddenSummaryFragments"
                      value="^@return the *|^This method returns |^A [{]@code [a-zA-Z0-9]+[}]( is a )"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="JavadocParagraph">
            <property name="allowNewlineParagraph" value="false"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="RequireEmptyLineBeforeBlockTagGroup">
            <property name="severity" value="warning"/>
        </module>
        <module name="AtclauseOrder">
            <property name="tagOrder" value="@param, @return, @throws, @deprecated"/>
            <property name="target"
                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF, VARIABLE_DEF"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="JavadocMethod">
            <property name="accessModifiers" value="public"/>
            <property name="allowMissingParamTags" value="true"/>
            <property name="allowMissingReturnTag" value="true"/>
            <property name="allowedAnnotations" value="Override, Test"/>
            <property name="tokens" value="METHOD_DEF, CTOR_DEF, ANNOTATION_FIELD_DEF, COMPACT_CTOR_DEF"/>
        </module>
        <module name="MissingJavadocMethod">
            <property name="scope" value="protected"/>
            <property name="allowMissingPropertyJavadoc" value="true"/>
            <property name="allowedAnnotations" value="Override, Test"/>
            <property name="tokens" value="METHOD_DEF, CTOR_DEF, ANNOTATION_FIELD_DEF,
                                   COMPACT_CTOR_DEF"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <property name="checks" value="MissingJavadocMethod"/>
            <property name="query" value="//*[self::METHOD_DEF or self::CTOR_DEF
                                 or self::ANNOTATION_FIELD_DEF or self::COMPACT_CTOR_DEF]
                                 [ancestor::*[self::INTERFACE_DEF or self::CLASS_DEF
                                 or self::RECORD_DEF or self::ENUM_DEF]
                                 [not(./MODIFIERS/LITERAL_PUBLIC)]]"/>
        </module>
        <module name="MissingJavadocType">
            <property name="scope" value="protected"/>
            <property name="tokens"
                      value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF,
                      RECORD_DEF, ANNOTATION_DEF"/>
            <property name="excludeScope" value="nothing"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="MethodName">
            <property name="format"
                      value="^(?![a-z]$)(?![a-z][A-Z])[a-z][a-z0-9]*(?:[A-Z][a-z0-9]*)*(?:_[0-9]+)*$"/>
            <message key="name.invalidPattern"
                     value="Method name ''{0}'' must match pattern ''{1}''."/>
        </module>
        <module name="SuppressionXpathSingleFilter">
            <property name="checks" value="MethodName"/>
            <property name="query" value="//METHOD_DEF[
                                     ./MODIFIERS/ANNOTATION//IDENT[contains(@text, 'Test')]
                                   ]/IDENT"/>
            <property name="message" value="'[a-z][a-z0-9][a-zA-Z0-9]*(?:_[a-z][a-z0-9][a-zA-Z0-9]*)*'"/>
        </module>
        <module name="SingleLineJavadoc">
            <property name="severity" value="warning"/>
        </module>
        <module name="TodoComment">
            <property name="format" value="^[ \t]*(?!TODO:)(?i:TODO)\b:?"/>
            <message key="todo.match"
                     value="''TODO:'' must be written in all caps and followed by a colon."/>
            <property name="severity" value="warning"/>
        </module>
        <module name="EmptyCatchBlock">
            <property name="commentFormat" value="\w+"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="CommentsIndentation">
            <property name="tokens" value="SINGLE_LINE_COMMENT, BLOCK_COMMENT_BEGIN"/>
        </module>
        <!-- https://checkstyle.org/filters/suppressionxpathfilter.html -->
        <module name="SuppressionXpathFilter">
            <property name="file" value="${org.checkstyle.google.suppressionxpathfilter.config}"
                      default="checkstyle-xpath-suppressions.xml" />
            <property name="optional" value="true"/>
        </module>
        <module name="SuppressWarningsHolder" />
        <module name="SuppressionCommentFilter">
            <property name="offCommentFormat" value="CHECKSTYLE.OFF\: ([\w\|]+)" />
            <property name="onCommentFormat" value="CHECKSTYLE.ON\: ([\w\|]+)" />
            <property name="checkFormat" value="$1" />
        </module>
        <module name="SuppressWithNearbyCommentFilter">
            <property name="commentFormat" value="CHECKSTYLE.SUPPRESS\: ([\w\|]+)"/>
            <!-- $1 refers to the first match group in the regex defined in commentFormat -->
            <property name="checkFormat" value="$1"/>
            <!-- The check is suppressed in the next line of code after the comment -->
            <property name="influenceFormat" value="1"/>
        </module>
    </module>
</module>