LoChat/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">

<!--
    Google Java Style configuration for LoChat.
    Based on Google Java Style Guide:
    https://google.github.io/styleguide/javaguide.html
-->
<module name="Checker">
    <property name="charset" value="UTF-8"/>
    <property name="severity" value="warning"/>
    <property name="fileExtensions" value="java"/>

    <!-- File length: max 600 lines -->
    <module name="FileLength">
        <property name="max" value="600"/>
    </module>

    <!-- Line length: max 100 characters (Google style) -->
    <module name="LineLength">
        <property name="max" value="100"/>
        <property name="ignorePattern"
            value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
    </module>

    <!-- No tabs allowed (Google style: spaces only) -->
    <module name="FileTabCharacter"/>

    <module name="TreeWalker">

        <!-- ========== Google Style: Indentation ========== -->
        <!-- Basic offset: 2, continuation indent: 4 (Google style) -->
        <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="arrayInitIndent" value="2"/>
            <property name="lineWrappingIndentation" value="4"/>
            <property name="forceStrictCondition" value="false"/>
        </module>

        <!-- ========== Google Style: Braces ========== -->
        <!-- Braces required for if/for/while/do (Google style) -->
        <module name="NeedBraces"/>
        <!-- Left brace at end of line (Google style) -->
        <module name="LeftCurly">
            <property name="option" value="eol"/>
        </module>
        <!-- Right brace alone on line (Google style) -->
        <module name="RightCurly">
            <property name="option" value="alone"/>
        </module>

        <!-- ========== Google Style: Whitespace ========== -->
        <module name="WhitespaceAround">
            <property name="allowEmptyConstructors" value="true"/>
            <property name="allowEmptyMethods" value="true"/>
            <property name="allowEmptyTypes" value="true"/>
            <property name="allowEmptyLoops" value="true"/>
            <property name="allowEmptyLambdas" value="true"/>
            <property name="allowEmptyCatches" value="true"/>
        </module>
        <module name="WhitespaceAfter"/>
        <module name="NoWhitespaceBefore">
            <property name="tokens" value="COMMA, SEMI, POST_INC, POST_DEC, DOT, METHOD_REF"/>
        </module>
        <module name="NoWhitespaceAfter">
            <property name="tokens"
                value="BNOT, DEC, DOT, INC, LNOT, UNARY_MINUS, UNARY_PLUS, ARRAY_DECLARATOR"/>
        </module>
        <module name="GenericWhitespace"/>
        <module name="MethodParamPad"/>
        <module name="ParenPad"/>
        <module name="TypecastParenPad"/>
        <module name="NoLineWrap"/>

        <!-- ========== Google Style: Naming ========== -->
        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
        </module>
        <module name="TypeName"/>
        <module name="MethodName"/>
        <module name="MemberName"/>
        <module name="ParameterName"/>
        <module name="LocalVariableName"/>
        <module name="ConstantName"/>
        <module name="CatchParameterName"/>
        <module name="ClassTypeParameterName"/>
        <module name="MethodTypeParameterName"/>
        <module name="InterfaceTypeParameterName"/>
        <module name="LambdaParameterName"/>
        <module name="PatternVariableName"/>
        <module name="RecordComponentName"/>
        <module name="LocalFinalVariableName"/>
        <module name="StaticVariableName"/>
        <module name="AbbreviationAsWordInName">
            <property name="allowedAbbreviationLength" value="0"/>
            <property name="ignoreFinal" value="false"/>
            <property name="allowedAbbreviations" value="IO, URL, HTML, XML, JSON, SQL, API, PM, RP, GUI, ID"/>
        </module>

        <!-- ========== Google Style: Imports ========== -->
        <module name="AvoidStarImport"/>
        <module name="UnusedImports"/>
        <module name="RedundantImport"/>
        <module name="ImportOrder">
            <property name="groups" value="com,net,org,java,javax"/>
            <property name="ordered" value="true"/>
            <property name="separated" value="true"/>
            <property name="option" value="top"/>
            <property name="sortStaticImportsAlphabetically" value="true"/>
        </module>

        <!-- ========== Google Style: Modifiers ========== -->
        <module name="ModifierOrder"/>
        <module name="RedundantModifier"/>

        <!-- ========== Code Quality ========== -->
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>
        <module name="StringLiteralEquality"/>
        <module name="DefaultComesLast"/>
        <module name="MultipleVariableDeclarations"/>
        <module name="FallThrough"/>
        <module name="HideUtilityClassConstructor"/>
        <module name="OneTopLevelClass"/>
        <module name="OneStatementPerLine"/>
        <module name="EmptyBlock">
            <property name="option" value="text"/>
        </module>
        <module name="EmptyCatchBlock">
            <property name="exceptionVariableName" value="expected|ignore"/>
        </module>
        <module name="MissingSwitchDefault"/>
        <module name="UpperEll"/>
        <module name="ArrayTypeStyle"/>
        <module name="CommentsIndentation"/>
        <module name="UnnecessaryParentheses"/>

        <!-- ========== Metrics ========== -->
        <module name="MethodLength">
            <property name="max" value="60"/>
            <property name="countEmpty" value="false"/>
        </module>
        <module name="CyclomaticComplexity">
            <property name="max" value="15"/>
        </module>
        <module name="ParameterNumber">
            <property name="max" value="7"/>
        </module>
        <module name="NestedIfDepth">
            <property name="max" value="3"/>
        </module>
        <module name="NestedTryDepth">
            <property name="max" value="2"/>
        </module>

        <!-- ========== Google Style: Javadoc ========== -->
        <module name="JavadocMethod">
            <property name="accessModifiers" value="public, protected"/>
            <property name="allowMissingParamTags" value="false"/>
            <property name="allowMissingReturnTag" value="false"/>
            <property name="allowedAnnotations" value="Override, Test"/>
            <property name="tokens" value="METHOD_DEF, CTOR_DEF, ANNOTATION_FIELD_DEF"/>
        </module>
        <module name="MissingJavadocMethod">
            <property name="scope" value="public"/>
            <property name="minLineCount" value="2"/>
            <property name="allowedAnnotations" value="Override, Test"/>
            <property name="tokens" value="METHOD_DEF, CTOR_DEF"/>
        </module>
        <module name="MissingJavadocType">
            <property name="scope" value="public"/>
        </module>
        <module name="JavadocType">
            <property name="scope" value="public"/>
        </module>
        <module name="JavadocStyle"/>
        <module name="NonEmptyAtclause"/>

    </module>
</module>