discord-bot/config/checkstyle/checkstyle.xml

<?xml version="1.0"?>
<!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="warning"/>
    <property name="fileExtensions" value="java"/>

    <module name="BeforeExecutionExclusionFileFilter">
        <property name="fileNamePattern" value=".*[\\/]src[\\/]test[\\/].*"/>
    </module>

    <module name="FileLength">
        <property name="max" value="200"/>
    </module>

    <module name="SuppressWarningsFilter"/>

    <module name="LineLength">
        <property name="max" value="120"/>
        <property name="ignorePattern"
            value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
    </module>

    <module name="TreeWalker">
        <module name="SuppressWarningsHolder"/>

        <module name="MethodLength">
            <property name="max" value="80"/>
            <property name="countEmpty" value="false"/>
        </module>

        <module name="CyclomaticComplexity">
            <property name="max" value="20"/>
        </module>

        <module name="ParameterNumber">
            <property name="max" value="7"/>
        </module>

        <module name="AvoidStarImport"/>
        <module name="UnusedImports"/>
        <module name="RedundantImport"/>

        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-zA-Z][a-zA-Z0-9]*)*$"/>
        </module>
        <module name="TypeName"/>
        <module name="MethodName"/>
        <module name="MemberName"/>
        <module name="ParameterName"/>
        <module name="LocalVariableName"/>
        <module name="ConstantName">
            <property name="format" value="^log$|^[A-Z][A-Z0-9]*(_[A-Z0-9]+)*$"/>
        </module>

        <module name="NeedBraces"/>
        <module name="LeftCurly"/>
        <module name="RightCurly"/>

        <module name="ModifierOrder"/>
        <module name="RedundantModifier"/>
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>
        <module name="StringLiteralEquality"/>
        <module name="DefaultComesLast"/>
        <module name="MultipleVariableDeclarations"/>
        <module name="OneStatementPerLine"/>
        <module name="FallThrough"/>
        <module name="HideUtilityClassConstructor"/>
        <module name="OneTopLevelClass"/>
        <module name="UpperEll"/>
        <module name="ArrayTypeStyle"/>
        <module name="MissingSwitchDefault"/>
        <module name="OuterTypeFilename"/>

        <module name="EmptyBlock">
            <property name="option" value="text"/>
        </module>
        <module name="EmptyCatchBlock">
            <property name="exceptionVariableName" value="expected|ignore"/>
        </module>

        <module name="EqualsAvoidNull"/>
        <module name="NoFinalizer"/>
        <module name="NoClone"/>
        <module name="PackageDeclaration"/>

        <module name="NPathComplexity">
            <property name="max" value="50"/>
        </module>
        <module name="NestedIfDepth">
            <property name="max" value="3"/>
        </module>
        <module name="NestedForDepth">
            <property name="max" value="2"/>
        </module>
        <module name="NestedTryDepth">
            <property name="max" value="2"/>
        </module>
        <module name="ClassDataAbstractionCoupling">
            <property name="max" value="25"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="ClassFanOutComplexity">
            <property name="max" value="30"/>
            <property name="severity" value="warning"/>
        </module>

        <module name="MagicNumber">
            <property name="ignoreNumbers" value="-1, 0, 1, 2"/>
            <property name="ignoreHashCodeMethod" value="true"/>
            <property name="ignoreAnnotation" value="true"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="Regexp">
            <property name="format" value="System\.(out|err)\.print"/>
            <property name="illegalPattern" value="true"/>
            <property name="message" value="Use a logger instead of System.out/err"/>
        </module>
        <module name="Regexp">
            <property name="format" value="\.printStackTrace\(\)"/>
            <property name="illegalPattern" value="true"/>
            <property name="message" value="Use a logger instead of printStackTrace"/>
        </module>
        <module name="IllegalThrows"/>
        <module name="IllegalCatch">
            <property name="illegalClassNames"
                value="java.lang.Exception, java.lang.Throwable, java.lang.RuntimeException"/>
        </module>

        <module name="WhitespaceAround"/>
        <module name="WhitespaceAfter"/>
        <module name="NoWhitespaceBefore"/>
        <module name="MissingOverride"/>
        <module name="MissingDeprecated">
            <property name="severity" value="warning"/>
        </module>
        <module name="FinalLocalVariable">
            <property name="validateEnhancedForLoopVariable" value="true"/>
            <property name="severity" value="warning"/>
        </module>

        <module name="Indentation">
            <property name="basicOffset" value="2"/>
            <property name="braceAdjustment" value="0"/>
            <property name="caseIndent" value="2"/>
            <property name="throwsIndent" value="4"/>
            <property name="lineWrappingIndentation" value="4"/>
            <property name="arrayInitIndent" value="2"/>
        </module>
    </module>
</module>