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="severity" value="error" />

	<module name="TreeWalker">
		<property name="tabWidth" value="3" />

		<module name="RegexpSinglelineJava">
			<property name="format" value="^\t*(?! \*) " />
			<property name="message"
				value="Indent must use tab characters" />
		</module>

		<!-- Annotations -->
		<module name="AnnotationUseStyle" />
		<module name="MissingDeprecated">
			<property name="skipNoJavadoc" value="true" />
		</module>
		<module name="MissingOverride" />
		<module name="PackageAnnotation" />

		<!-- Blocks -->
		<module name="EmptyCatchBlock">
			<property name="exceptionVariableName"
				value="expected|ignore" />
		</module>
		<module name="LeftCurly">
			<property name="option" value="nlow" />
			<property name="ignoreEnums" value="false" />
		</module>
		<module name="NeedBraces">
			<property name="allowSingleLineStatement" value="true" />
		</module>
		<module name="RightCurly" />

		<!-- Class design -->
		<module name="HideUtilityClassConstructor" />
		<module name="InnerTypeLast" />
		<module name="InterfaceIsType" />
		<module name="OneTopLevelClass" />

		<!-- Coding -->
		<module name="CovariantEquals" />
		<module name="DeclarationOrder" />
		<module name="DefaultComesLast" />
		<module name="EmptyStatement" />
		<module name="EqualsHashCode" />
		<module name="ExplicitInitialization" />
		<module name="MissingSwitchDefault" />
		<module name="MultipleStringLiterals">
			<property name="allowedDuplicates" value="4"/>
		</module>
		<module name="OneStatementPerLine" />
		<module name="OverloadMethodsDeclarationOrder" />
		<module name="PackageDeclaration" />
		<module name="StringLiteralEquality" />
		<module name="UnnecessaryParentheses" />

		<!-- Imports -->
		<module name="AvoidStarImport" />
		<module name="CustomImportOrder">
			<property name="customImportOrderRules"
				value="THIRD_PARTY_PACKAGE###STANDARD_JAVA_PACKAGE###STATIC" />
		</module>
		<module name="RedundantImport" />
		<module name="UnusedImports">
			<property name="processJavadoc" value="false" />
		</module>

		<!-- Javadoc -->
		<module name="AtclauseOrder" />

		<!-- Misc -->
		<module name="ArrayTypeStyle" />
		<module name="OuterTypeFilename" />
		<module name="CommentsIndentation" />
		<module name="Indentation">
			<property name="basicOffset" value="3" />
			<property name="caseIndent" value="0" />
			<property name="lineWrappingIndentation" value="6" />
		</module>
		<module name="TodoComment">
			<property name="format" value="(TODO)|(FIXME)" />
		</module>
		<module name="UpperEll" />

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

		<!-- Naming -->
		<module name="ConstantName" />

		<!-- Sizes -->
		<module name="LineLength">
			<property name="max" value="120" />
		</module>
	</module>

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

	<module name="NewlineAtEndOfFile">
		<property name="lineSeparator" value="lf" />
	</module>
	<module name="UniqueProperties" />
</module>