checkstyle.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC
    "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
        "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
<module name="Checker">
    <!-- Tabs are strictly banned -->
    <module name="FileTabCharacter" />
    <module name="TreeWalker">
        <!-- Important basics -->
        <module name="OuterTypeFilename" />
        <module name="HideUtilityClassConstructor" />
        <module name="CovariantEquals" />
        <module name="EqualsHashCode" />
        <module name="NestedTryDepth">
            <property name="max" value="2" />
        </module>
        <module name="SuperFinalize" />
        <module name="LeftCurly">
            <!-- Left brace never goes on another line -->
            <property name="option" value="eol" />
        </module>
        <module name="DefaultComesLast" />
        <module name="GenericWhitespace" />
        <module name="ClassTypeParameterName">
            <property name="format" value="^[A-Z][a-zA-Z0-9]*$" />
        </module>
        <module name="LocalFinalVariableName" />
        <module name="LocalVariableName">
            <property name="format" value="^[a-z_][a-zA-Z0-9]*$" />
        </module>
        <module name="MemberName">
            <property name="format" value="^[a-zA-Z0-9]*$" />
        </module>
        <module name="MethodName">
            <property name="format" value="^[a-z][a-zA-Z0-9]*$" />
        </module>
        <module name="ParameterName" />
    </module>
</module>