checkstyle.xml

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

<module name="Checker">
    <module name="SuppressionFilter">
        <property name="file" value="checkstyle_suppressions.xml"/>
    </module>
    <module name="FileTabCharacter"/>
    <module name="RegexpSingleline">
        <property name="format" value="\s+$"/>
        <property name="message" value="Line has trailing spaces."/>
    </module>
    <module name="RegexpMultiline">
        <property name="format" value="\r"/>
        <property name="message" value="Contains carriage return \r"/>
    </module>
    <module name="TreeWalker">
        <module name="Indentation"/>
    </module>
    <module name="RegexpHeader">
        <property name="id" value="header-check" />
        <property name="headerFile" value="checkstyle_header.txt"/>
        <property name="multiLines" value="2"/>
    </module>
</module>