checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
        "-//Checkstyle//DTD Checkstyle Configuration 1.3//EN"
        "https://checkstyle.org/dtds/configuration_1_3.dtd">

<!-- Checkstyle configuration that checks the sun coding conventions from:
	- the Java Language Specification at http://java.sun.com/docs/books/jls/second_edition/html/index.html
	- the Sun Code Conventions at http://java.sun.com/docs/codeconv/ - the Javadoc
	guidelines at http://java.sun.com/j2se/javadoc/writingdoccomments/index.html
	- the JDK Api documentation http://java.sun.com/j2se/docs/api/index.html
	- some best practices Checkstyle is very configurable. Be sure to read the
	documentation at http://checkstyle.sf.net (or in your downloaded distribution).
	Most Checks are configurable, be sure to consult the documentation. To completely
	disable a check, just comment it out or delete it from the file. Finally,
	it is worth reading the documentation. -->

<module name="Checker">
    <module name="Translation"/>
    <module name="FileLength"/>
    <module name="NewlineAtEndOfFile">
        <property name="fileExtensions" value="java"/>
    </module>

    <module name="UniqueProperties"/>

    <module name="LineLength">
        <property name="max" value="180"/>
        <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://"/>
    </module>

    <module name="SuppressWarningsFilter"/>

    <module name="TreeWalker">
        <module name="SuppressWarningsHolder"/>
        <module name="AnnotationLocation">
            <property name="allowSamelineSingleParameterlessAnnotation" value="false"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="MissingDeprecated">
            <property name="severity" value="warning"/>
        </module>
        <module name="AvoidNestedBlocks"/>
        <module name="EmptyBlock"/>
        <module name="EmptyLineSeparator">
            <property name="allowMultipleEmptyLines" value="false"/>
            <property name="allowMultipleEmptyLinesInsideClassMembers" value="false"/>
            <property name="tokens" value="CLASS_DEF, METHOD_DEF"/>
        </module>
        <module name="EmptyCatchBlock"/>
        <module name="LeftCurly">
            <property name="tokens" value="CLASS_DEF,INTERFACE_DEF,ANNOTATION_DEF,CTOR_DEF,METHOD_DEF"/>
        </module>
        <module name="NeedBraces"/>
        <module name="RightCurly"/>
        <module name="FinalClass"/>
        <module name="HideUtilityClassConstructor"/>
        <module name="InterfaceIsType"/>
        <module name="CovariantEquals"/>
        <module name="DefaultComesLast"/>
        <module name="EmptyStatement"/>
        <module name="EqualsAvoidNull">
            <property name="severity" value="warning"/>
        </module>
        <module name="EqualsHashCode"/>
        <module name="HiddenField">
            <property name="ignoreSetter" value="true"/>
            <property name="setterCanReturnItsClass" value="true"/>
            <property name="ignoreConstructorParameter" value="true"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="IllegalCatch"/>
        <module name="IllegalThrows"/>
        <module name="InnerAssignment">
            <property name="severity" value="warning"/>
        </module>
        <module name="MissingSwitchDefault">
        </module>
        <module name="MultipleStringLiterals">
            <property name="allowedDuplicates" value="2"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="OneStatementPerLine"/>
        <module name="PackageDeclaration"/>
        <module name="SimplifyBooleanExpression">
            <property name="severity" value="warning"/>
        </module>
        <module name="SimplifyBooleanReturn">
            <property name="severity" value="warning"/>
        </module>
        <module name="StringLiteralEquality"/>
        <module name="UnnecessaryParentheses"/>

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

        <module name="OuterTypeFilename"/>
        <module name="UpperEll"/>

        <module name="ModifierOrder">
            <property name="severity" value="warning"/>
        </module>
        <module name="RedundantModifier">
            <property name="severity" value="warning"/>
        </module>

        <module name="ConstantName">
            <property name="format" value="^(to[A-Z][a-zA-Z]+|([A-Z_]+))$"/>
        </module>
        <module name="MemberName"/>
        <module name="MethodName"/>
        <module name="PackageName"/>
        <module name="ParameterName"/>
        <module name="StaticVariableName"/>
        <module name="TypeName"/>
        <module name="EnumValueName"/>

        <module name="MethodLength">
            <property name="severity" value="warning"/>
        </module>
        <module name="ParameterNumber">
            <property name="severity" value="warning"/>
        </module>

        <module name="WhitespaceAround"/>
        <module name="TodoComment">
            <property name="format" value="(TODO)|(FIXME)"/>
            <property name="severity" value="warning"/>
        </module>
        <module name="GenericWhitespace"/>
        <module name="NoWhitespaceBefore">
            <property name="tokens" value="DOT"/>
            <property name="allowLineBreaks" value="true"/>
        </module>
        <module name="NoWhitespaceAfter">
            <property name="tokens" value="DOT"/>
            <property name="allowLineBreaks" value="false"/>
        </module>
    </module>
</module>