public static Set<Class<?>> findOnClassPath(String packageName, List<Class<?>> exclusions,
      List<Class<?>> selectors) {
    return ClasspathScannerUtils.findOnClassPath(ClasspathScannerUtils.class.getClassLoader(),
        packageName, exclusions, selectors);
  }
Scans the classpath for classes based on the provided arguments

@param packageName
         the package to be scanned
@param exclusions
         a list with classes excluded from the result
@param selectors
         a list with annotation and interface classes that identify classes
         to be found (lookup criteria)
@return a list of classes from the classpath that match the lookup criteria
ambari-server/src/main/java/org/apache/ambari/server/cleanup/ClasspathScannerUtils.java