code: protected void initCache(ClassTraversal traversal) {
      if (m_CacheNames == null)
        m_CacheNames = new HashMap<>();
      if (m_CacheClasses == null)
        m_CacheClasses = new HashMap<>();
      if (m_BlackListed == null)
        m_BlackListed = new HashSet<>();
      if (m_Cache == null)
        m_Cache = newClassCache(traversal);
    }
docs: initializes the cache for the classnames.
  
  @param traversal	how to traverse the classes, can be null