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 for CCSDS 124.0-B-1 Java implementation.
    Based on Google Java Style Guide with minor adjustments.
-->
<module name="Checker">
    <property name="charset" value="UTF-8"/>
    <property name="severity" value="error"/>
    <property name="fileExtensions" value="java"/>

    <!-- File length -->
    <module name="FileLength">
        <property name="max" value="2000"/>
    </module>

    <!-- No tabs -->
    <module name="FileTabCharacter">
        <property name="eachLine" value="true"/>
    </module>

    <!-- Trailing whitespace -->
    <module name="RegexpSingleline">
        <property name="format" value="\s+$"/>
        <property name="message" value="Trailing whitespace"/>
    </module>

    <!-- Line length (must be at Checker level, not TreeWalker) -->
    <module name="LineLength">
        <property name="max" value="120"/>
        <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://"/>
    </module>

    <module name="TreeWalker">
        <!-- Naming conventions -->
        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-z][a-z0-9]*)*$"/>
        </module>
        <module name="TypeName"/>
        <module name="MethodName"/>
        <module name="ConstantName"/>
        <module name="LocalVariableName"/>
        <module name="MemberName"/>
        <module name="ParameterName"/>
        <module name="StaticVariableName"/>

        <!-- Imports -->
        <module name="AvoidStarImport"/>
        <module name="UnusedImports"/>
        <module name="RedundantImport"/>

        <!-- Whitespace -->
        <module name="WhitespaceAround">
            <property name="allowEmptyConstructors" value="true"/>
            <property name="allowEmptyMethods" value="true"/>
            <property name="allowEmptyTypes" value="true"/>
            <property name="allowEmptyLoops" value="true"/>
        </module>
        <module name="WhitespaceAfter"/>
        <module name="NoWhitespaceBefore"/>
        <module name="GenericWhitespace"/>
        <module name="MethodParamPad"/>
        <module name="ParenPad"/>
        <module name="TypecastParenPad"/>

        <!-- Blocks -->
        <module name="LeftCurly"/>
        <module name="RightCurly"/>
        <module name="NeedBraces"/>
        <module name="EmptyBlock">
            <property name="option" value="TEXT"/>
        </module>

        <!-- Coding -->
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>
        <module name="StringLiteralEquality"/>
        <module name="OneStatementPerLine"/>
        <module name="MultipleVariableDeclarations"/>
        <module name="ArrayTypeStyle"/>
        <module name="MissingSwitchDefault"/>
        <module name="FallThrough"/>
        <module name="UpperEll"/>
        <module name="ModifierOrder"/>
        <module name="RedundantModifier"/>

        <!-- Javadoc - require on public methods -->
        <module name="MissingJavadocMethod">
            <property name="scope" value="public"/>
            <property name="allowMissingPropertyJavadoc" value="true"/>
            <property name="allowedAnnotations" value="Override,Test,BeforeEach,AfterEach,BeforeAll,AfterAll"/>
        </module>
        <module name="MissingJavadocType">
            <property name="scope" value="public"/>
        </module>
        <module name="JavadocMethod">
            <property name="allowMissingParamTags" value="true"/>
            <property name="allowMissingReturnTag" value="true"/>
        </module>

        <!-- Indentation -->
        <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>