checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
        "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
        "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">

<module name="Checker">

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

    <property name="fileExtensions" value="java, properties, xml"/>

    <module name="BeforeExecutionExclusionFileFilter">
        <property name="fileNamePattern" value="module\-info\.java$"/>
    </module>
    
    <!-- Checks for Size Violations.                    -->
    <!-- See http://checkstyle.sf.net/config_sizes.html -->
    <module name="FileLength"/>

    <module name="LineLength">
        <property name="fileExtensions" value="java"/>
        <property name="max" value="100"/>
    </module>
    <!-- Checks for Headers                                -->
    <!-- See http://checkstyle.sf.net/config_header.html   -->
    <!-- <module name="Header"> -->
    <!--   <property name="headerFile" value="${checkstyle.header.file}"/> -->
    <!--   <property name="fileExtensions" value="java"/> -->
    <!-- </module> -->

    <module name="TreeWalker">

        <module name="DeclarationOrder"/>

        <module name="EmptyLineSeparator">
            <property name="tokens" value="
            CLASS_DEF, ENUM_DEF, INTERFACE_DEF, CTOR_DEF, STATIC_INIT, INSTANCE_INIT, VARIABLE_DEF, METHOD_DEF"/>
            <property name="allowNoEmptyLineBetweenFields" value="true"/>
            <property name="allowMultipleEmptyLines" value="false"/>
            <property name="allowMultipleEmptyLinesInsideClassMembers" value="false"/>
        </module>

        <module name="VisibilityModifier"/>
        <!-- Checks for Naming Conventions.                  -->
        <!-- See http://checkstyle.sf.net/config_naming.html -->
        <module name="ConstantName"/>
        <!--<module name="LocalFinalVariableName"/>-->
        <module name="LocalVariableName"/>
        <module name="MemberName"/>
        <module name="MethodName"/>
        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-z0-9]*)*$"/>
        </module>
        <module name="ParameterName"/>
        <module name="StaticVariableName"/>
        <module name="TypeName"/>

        <!-- Checks for Size Violations.                    -->
        <!-- See http://checkstyle.sf.net/config_sizes.html -->
        <!--<module name="LineLength"/>-->
        <module name="MethodLength"/>
        <module name="ParameterNumber"/>

        <!-- Checks for whitespace                               -->
        <!-- See http://checkstyle.sf.net/config_whitespace.html -->
        <module name="EmptyForIteratorPad"/>
        <module name="GenericWhitespace"/>
        <module name="MethodParamPad"/>
        <module name="NoWhitespaceAfter"/>
        <module name="NoWhitespaceBefore"/>
        <module name="OperatorWrap"/>
        <module name="ParenPad"/>
        <module name="TypecastParenPad"/>
        <module name="WhitespaceAfter"/>
        <module name="WhitespaceAround"/>

        <!-- Modifier Checks                                    -->
        <!-- See http://checkstyle.sf.net/config_modifiers.html -->

        <!-- Checks for blocks. You know, those {}'s         -->
        <!-- See http://checkstyle.sf.net/config_blocks.html -->
        <module name="AvoidNestedBlocks"/>
        <module name="EmptyBlock"/>
        <module name="LeftCurly"/>
        <module name="NeedBraces"/>
        <module name="RightCurly"/>

        <!-- Checks for common coding problems               -->
        <!-- See http://checkstyle.sf.net/config_coding.html -->
        <!--<module name="AvoidInlineConditionals"/>-->
        <module name="EmptyStatement"/>
        <module name="EqualsHashCode"/>
        <!--<module name="HiddenField"/>-->
        <module name="IllegalInstantiation"/>
        <module name="InnerAssignment"/>
        <!--<module name="MagicNumber"/>-->
        <module name="MissingSwitchDefault"/>
        <module name="SimplifyBooleanExpression"/>
        <module name="SimplifyBooleanReturn"/>

        <!-- Checks for class design                         -->
        <!-- See http://checkstyle.sf.net/config_design.html -->
        <!--<module name="DesignForExtension"/>-->
        <!--<module name="FinalClass"/>-->
        <!--<module name="HideUtilityClassConstructor"/>-->
        <module name="InterfaceIsType"/>

        <!-- Miscellaneous other checks.                   -->
        <!-- See http://checkstyle.sf.net/config_misc.html -->
        <module name="ArrayTypeStyle"/>
        <!--<module name="FinalParameters"/>-->
        <module name="TodoComment"/>
        <module name="UpperEll"/>

    </module>

</module>