checkstyle.xml

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE module PUBLIC
	"-//Puppy Crawl//DTD Package Names 1.0//EN"
	"http://www.puppycrawl.com/dtds/configuration_1_1.dtd">

<module name="Checker">
	<!-- Check that package.html exists -->
	<module name="PackageHtml"/>

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

		<!-- Import checks -->
		<module name="AvoidStarImport"/>
		<module name="ConstantName"/>
		<module name="RedundantImport"/>
		<module name="UnusedImports"/>

		<!-- Modifier checks -->
		<module name="RedundantModifier">
			<property name="tokens" value="METHOD_DEF"/>
		</module>
		<module name="VisibilityModifier">
			<property name="packageAllowed" value="true"/>
			<property name="protectedAllowed" value="true"/>
		</module>

		<!-- Whitespace checks -->
		<module name="ParenPad">
			<property name="option" value="space"/>
            <property name="tokens" value="CTOR_CALL, METHOD_CALL, SUPER_CTOR_CALL"/>
		</module>

        <module name="TabCharacter"/>

		<!-- Javadoc checks -->
		<module name="JavadocType">
			<property name="versionFormat" value=".*"/>
		</module>

		<!-- Blocks -->
		<module name="LeftCurly">
			<property name="option" value="eol"/>
		</module>
		<module name="RightCurly">
			<property name="option" value="same"/>
		</module>
        <!-- It seems to be a good idea to concantenate strings with the '+' on
             the next line because it makes it easier to add, extend or remove parts of the string -->
		<module name="OperatorWrap">
			<property name="option" value="nl"/>
			<property name="tokens" value="PLUS"/>
		</module>
		<module name="NeedBraces"/>
		<module name="EmptyBlock">
			<property name="option" value="text"/>
		</module>

		<!-- Naming conventions -->
		<module name="ConstantName"/>
		<module name="ParameterName">
			<property name="format" value="^[a-z][a-zA-Z0-9_]*$"/>
		</module>
		<module name="StaticVariableName">
			<property name="format" value="^[a-z][a-zA-Z0-9]*$"/>
		</module>
		<module name="LocalVariableName">
			<property name="format" value="^[a-z][a-zA-Z0-9_]*$"/>
		</module>
		<module name="MemberName">
			<property name="format" value="^[a-z][a-zA-Z0-9]*$"/>
		</module>

		<!-- Size Violations -->
		<module name="FileLength">
			<property name="max" value="2000"/>
		</module>
		<module name="LineLength">
			<property name="max" value="320"/>
		</module>
		<module name="MethodLength">
			<property name="max" value="150"/>
		</module>
	</module>
</module>