private boolean isCategorizedClass(Class<?> c) {
      if (this.categoryAnnotation == null) {
        return true;
      }
      for (Class<?> cc : getCategoryAnnotations(c)) {
        if (cc.equals(this.categoryAnnotation)) {
          return true;
        }
      }
      return false;
    }
Filters both test classes and anything in the hadoop-compat modules
hbase-common/src/test/java/org/apache/hadoop/hbase/ClassTestFinder.java