This is a predefined ruleset for Maven coding conventions that can be used in Maven Checkstyle Plugin:

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    "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"

  Checkstyle configuration that checks the Maven coding conventions from:

<module name="Checker">

    <!-- BeforeExecutionFileFilters is required for sources that are based on java9 -->
    <module name="BeforeExecutionExclusionFileFilter">
        <property name="fileNamePattern" value="module\-info\.java$" />

    <!-- Checks whether files end with a new line.                        -->
    <!-- See -->
    <!-- module name="NewlineAtEndOfFile"/ -->

    <module name="FileLength"/>

    <!-- Checks for Headers                              -->
    <!-- See -->
    <module name="RegexpHeader">
      <property name="fileExtensions" value="java"/>
      <property name="headerFile" value="${checkstyle.header.file}"/>

    <module name="FileTabCharacter">
        <property name="eachLine" value="true"/>

    <!-- Line with trailing spaces (disabled as it's too noisy) -->
    <!--<module name="RegexpSingleline">
        <property name="format" value="\s+$"/>
        <property name="message" value="Line has trailing spaces."/>

    <module name="LineLength">
        <property name="max" value="120" />
        <property name="ignorePattern" value="@version|@see|@todo|TODO"/>

    <!-- Support CHECKSTYLE_OFF: regexp and CHECKSTYLE_ON: regexp comments to disable/enable some checks -->
    <!-- see -->
    <module name="SuppressWithPlainTextCommentFilter">
        <property name="offCommentFormat" value="CHECKSTYLE_OFF\: (.+)"/>
        <property name="onCommentFormat" value="CHECKSTYLE_ON\: (.+)"/>
        <property name="checkFormat" value="$1"/>

    <module name="TreeWalker">

        <property name="tabWidth" value="4"/>

        <!-- required for SuppressWarningsFilter (and other Suppress* rules not used here) -->
        <!-- see -->
        <module name="SuppressWarningsHolder"/>

        <module name="LeftCurly">
          <property name="option" value="nl"/>

        <module name="RightCurly">
          <property name="option" value="alone"/>

        <module name="MemberName" />

        <!-- Checks for Javadoc comments.                     -->
        <!-- See   -->
        To configure the check to use legacy package.html file when file is absent:
        <module name="JavadocPackage">
          <property name="allowLegacy" value="true"/>
        <module name="JavadocMethod">
          <property name="accessModifiers" value="public, protected"/>
          <property name="severity" value="warning"/>
        <module name="JavadocType">
          <property name="scope" value="protected"/>
          <property name="allowUnknownTags" value="true" />
        <module name="JavadocVariable">
          <property name="severity" value="info"/>
          <property name="scope" value="protected"/>

        <!-- Checks for Naming Conventions.                  -->
        <!-- See   -->
        <module name="ConstantName"/>
        <module name="LocalFinalVariableName"/>
        <module name="LocalVariableName"/>
        <module name="MethodName"/>
        <module name="PackageName"/>
        <module name="ParameterName"/>
        <module name="StaticVariableName"/>
        <module name="TypeName"/>

        <!-- Checks for imports                              -->
        <!-- See  -->
        <module name="AvoidStarImport"/>
        <module name="IllegalImport"/>
        <module name="RedundantImport"/>
        <module name="UnusedImports"/>

        <!-- Checks for Size Violations.                    -->
        <!-- See   -->
        <module name="MethodLength"/>
        <module name="ParameterNumber"/>

        <!-- Checks for whitespace                               -->
        <!-- See   -->
        <module name="EmptyForIteratorPad">
          <property name="option" value="space"/>
        <!-- module name="NoWhitespaceAfter"/ -->
        <!-- module name="NoWhitespaceBefore"/ -->
        <module name="OperatorWrap"/>
        <module name="ParenPad">
          <property name="option" value="space" />
        <module name="WhitespaceAfter"/>
        <module name="WhitespaceAround"/>
        <!-- module name="MethodParamPad"/ -->
        <module name="GenericWhitespace"/>

        <!-- Modifier Checks                                    -->
        <!-- See    -->
        <module name="ModifierOrder"/>
        <module name="RedundantModifier"/>

        <!-- Checks for blocks. You know, those {}'s         -->
        <!-- See   -->
        <module name="AvoidNestedBlocks"/>
        <module name="EmptyBlock">
          <property name="option" value="text"/>
        <module name="NeedBraces"/>

        <!-- Checks for common coding problems               -->
        <!-- See -->
        <!-- module name="AvoidInlineConditionals"/ -->
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <module name="HiddenField">
          <property name="severity" value="warning"/>
          <property name="ignoreSetter" value="true"/>
          <property name="setterCanReturnItsClass" value="true"/>
          <property name="ignoreConstructorParameter" value="true"/>
        <module name="IllegalInstantiation"/>
        <module name="InnerAssignment"/>
        <module name="MissingSwitchDefault"/>
        <module name="OneStatementPerLine"/>
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>
        <module name="UnusedLocalVariable"/>

        <!-- Checks for class design                         -->
        <!-- See   -->
        <!-- module name="DesignForExtension"/ -->
        <!-- module name="FinalClass"/ -->
        <!-- module name="HideUtilityClassConstructor"/ -->
        <module name="InterfaceIsType"/>
        <module name="VisibilityModifier">
          <property name="protectedAllowed" value="true"/>
          <property name="packageAllowed" value="true"/>

        <!-- Miscellaneous other checks.                   -->
        <!-- See -->
        <!-- module name="ArrayTypeStyle"/ -->
        <!-- module name="FinalParameters"/ -->
        <!-- Let todo plugin handle this.
        <module name="TodoComment"/>
        <module name="UpperEll"/>


    <!-- Support @SuppressWarnings (added in Checkstyle 5.7) -->
    <!-- see -->
    <module name="SuppressWarningsFilter"/>

    <!-- Checks properties file for a duplicated properties. -->
    <!-- See -->
    <module name="UniqueProperties"/>