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">

	<module name="RegexpSingleline">
		<property name="format" value="\s+$"/>
		<property name="minimum" value="0"/>
		<property name="maximum" value="0"/>
		<property name="message" value="No trailing spaces allowed"/>
		<property name="fileExtensions" value="java"/>
	</module>

	<module name="RegexpMultiline">
		<property name="format" value="System\s*\.(err|out)"/>
		<property name="message" value="Use Log instead of standard output"/>
	</module>

	<module name="TreeWalker">

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

		<module name="ConstantName"/>
		<module name="LocalFinalVariableName"/>
		<module name="LocalVariableName"/>
		<module name="MemberName"/>
		<module name="MethodName"/>
		<module name="PackageName"/>
		<module name="ParameterName"/>
		<module name="StaticVariableName"/>
		<module name="TypeName"/>

		<module name="AvoidStarImport"/>
		<module name="IllegalImport"/>
		<module name="RedundantImport"/>
		<module name="UnusedImports"/>

		<module name="ImportOrder">
			<property name="separated" value="true"/>
			<property name="option" value="top"/>
		</module>

		<module name="RegexpSinglelineJava">
			<property name="format" value="^\t* +\t*\S"/>
			<property name="message" value="Use tab character for code indentation"/>
			<property name="ignoreComments" value="true"/>
		</module>

		<module name="RegexpSinglelineJava">
			<property name="format" value="^\s*(&quot;([^&quot;])*(?&lt;!\\)&quot;|[^&quot;\t])+(\t|  )"/>
			<property name="message" value="No tabs or multiple whitespace characters except indentation allowed"/>
			<property name="ignoreComments" value="true"/>
		</module>

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

		<module name="ParameterNumber">
			<property name="max" value="6"/>
		</module>

		<module name="EmptyForIteratorPad"/>
		<module name="GenericWhitespace"/>
		<module name="MethodParamPad"/>

		<module name="NoWhitespaceAfter">
			<property name="tokens" value="BNOT, DEC, DOT, INC, LNOT, UNARY_MINUS, UNARY_PLUS"/>
		</module>

		<module name="NoWhitespaceBefore"/>
		<module name="OperatorWrap"/>
		<module name="ParenPad"/>
		<module name="TypecastParenPad"/>
		<module name="WhitespaceAfter"/>

		<module name="WhitespaceAround">
			<property name="allowEmptyConstructors" value="true"/>
			<property name="allowEmptyMethods" value="true"/>
		</module>

		<module name="ModifierOrder"/>
		<module name="RedundantModifier"/>

		<module name="EmptyBlock"/>

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

		<module name="NeedBraces"/>

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

		<module name="EmptyStatement"/>
		<module name="EqualsHashCode"/>
		<module name="MissingSwitchDefault"/>
		<module name="SimplifyBooleanExpression"/>
		<module name="SimplifyBooleanReturn"/>

		<module name="HideUtilityClassConstructor"/>

		<module name="ArrayTypeStyle"/>
		<module name="UpperEll"/>
		<module name="CovariantEquals"/>

	</module>

</module>