checkstyle.xml

<?xml version="1.0"?>
<!DOCTYPE module PUBLIC "-//Puppy Crawl//DTD Check Configuration 1.3//EN" "http://www.puppycrawl.com/dtds/configuration_1_3.dtd">
<module name="Checker">
  <property name="charset" value="UTF-8"/>
  <module name="TreeWalker">
    <!--check that only Accumulo 1.9 public APIs are imported-->
    <module name="RegexpSinglelineJava">
<!--      <property name="format" value="import\s+org\.apache\.accumulo\.(.*\.(impl|thrift|crypto)\..*|(?!core|minicluster|testing).*|core\.(?!client|conf|data|security|spi|iterators).*)"/>-->
      <property name="format" value="import\s+org\.apache\.accumulo\.(?!(core\.(client|data|iterators|security)|minicluster|hadoop)\.).*" />
      <property name="ignoreComments" value="true" />
      <property name="message" value="Accumulo non-public classes imported" />
    </module>
  </module>
</module>