checkstyle.xml

<!DOCTYPE module PUBLIC
        "-//Puppy Crawl//DTD Check Configuration 1.3//EN"
        "https://checkstyle.org/dtds/configuration_1_3.dtd">
<module name="Checker">
    <property name="charset" value="UTF-8" />
    <property name="severity" value="warning" />
    <!-- Checks for whitespace -->
    <!-- See https://checkstyle.sf.net/config_whitespace.html -->
    <module name="FileTabCharacter">
        <property name="eachLine" value="true" />
    </module>
    <module name="LineLength">
       <!-- needs extra, because Eclipse formatter ignores the ending left
            brace -->
       <property name="max" value="200" />
       <property name="ignorePattern" value="^package.*|^import.*|a href|href|http://|https://|ftp://" />
    </module>
    <module name="TreeWalker">
        <module name="RegexpSinglelineJava">
            <property name="format" value="\s+$" />
            <property name="message" value="Line has trailing whitespace." />
        </module>
        <module name="RegexpSinglelineJava">
            <property name="format" value="[@]see\s+[{][@]link" />
            <property name="message" value="Javadoc @see does not need @link: pick one or the other." />
        </module>
        <module name="OuterTypeFilename" />
        <module name="AvoidStarImport" />
        <module name="UnusedImports">
            <property name="processJavadoc" value="true" />
        </module>
        <module name="NoLineWrap" />
        <module name="LeftCurly" />
        <module name="RightCurly" />
        <module name="RightCurly">
            <property name="option" value="alone_or_singleline" />
            <property name="tokens" value="CLASS_DEF, METHOD_DEF, CTOR_DEF, LITERAL_FOR, LITERAL_WHILE, STATIC_INIT, INSTANCE_INIT" />
        </module>
        <module name="SeparatorWrap">
            <property name="tokens" value="DOT" />
            <property name="option" value="nl" />
        </module>
        <module name="SeparatorWrap">
            <property name="tokens" value="COMMA" />
            <property name="option" value="EOL" />
        </module>
        <module name="PackageName">
            <property name="format" value="^[a-z]+(\.[a-z][a-zA-Z0-9]*)*$" />
        </module>
        <module name="MethodTypeParameterName">
            <property name="format" value="(^[A-Z][0-9]?)$|([A-Z][a-zA-Z0-9]*[T]$)" />
        </module>
        <module name="MethodParamPad" />
        <module name="OperatorWrap">
            <property name="option" value="NL" />
            <property name="tokens" value="BAND, BOR, BSR, BXOR, DIV, EQUAL, GE, GT, LAND, LE, LITERAL_INSTANCEOF, LOR, LT, MINUS, MOD, NOT_EQUAL, QUESTION, SL, SR, STAR " />
        </module>
        <module name="AnnotationLocation">
            <property name="tokens" value="CLASS_DEF, INTERFACE_DEF, ENUM_DEF, METHOD_DEF, CTOR_DEF" />
        </module>
        <module name="AnnotationLocation">
            <property name="tokens" value="VARIABLE_DEF" />
            <property name="allowSamelineMultipleAnnotations" value="true" />
        </module>
        <module name="NonEmptyAtclauseDescription" />
        <module name="JavadocMethod">
            <property name="allowMissingParamTags" value="true" />
            <property name="allowMissingReturnTag" value="true" />
            <property name="allowedAnnotations" value="Override,Test,BeforeClass,AfterClass,Before,After" />
        </module>
        <module name="SingleLineJavadoc" />
    </module>
</module>