checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC
        "-//Puppy Crawl//DTD Check Configuration 1.2//EN"
        "http://www.puppycrawl.com/dtds/configuration_1_2.dtd">

<module name="Checker">
    <module name="FileTabCharacter"/>
    <module name="RegexpMultiline">
        <!-- match any call to TransformerFactory.newInstance(), ignoring whitespace -->
        <property name="format" value="\bTransformerFactory\s*\.\s*newInstance\(\s*\)"/>
        <property name="maximum" value="0" />
        <property name="message" value="Do not use TransformerFactory.newInstance(). Either use ApiTransformerFactory.newInstance() or use TransformerFactory.newInstance(String,ClassLoader)."/>
    </module>
    <module name="RegexpMultiline">
        <!-- match any call to org.hamcrest.CoreMatchers, ignoring whitespace -->
        <property name="format" value="\borg\s*\.\s*hamcrest\s*\.\s*CoreMatchers\b"/>
        <property name="maximum" value="0" />
        <property name="message" value="Use org.hamcrest.Matchers (from hamcrest-library) instead of org.hamcrest.CoreMatchers (from hamcrest-core)."/>
    </module>
    <module name="TreeWalker">
        <property name="cacheFile" value="target/cachefile"/>
        <!-- Requires unused imports to be cleaned up -->
        <module name="UnusedImports">
            <property name="processJavadoc" value="true"/>
        </module>
    </module>
    <module name="SuppressWithNearbyCommentFilter">
        <property name="commentFormat" value="CHECKSTYLE IGNORE (\w+) FOR NEXT (\d+) LINES"/>
        <property name="checkFormat" value="$1"/>
        <property name="influenceFormat" value="$2"/>
    </module>
</module>