code: @SuppressWarnings("unchecked")
    public List<CoreMap> getAnnotatedChunks(List<CoreLabel> tokens, int totalTokensOffset, Class textKey, Class labelKey)
    {
      return getAnnotatedChunks(tokens, totalTokensOffset, textKey, labelKey, null, null);
    }
docs: Find and annotate chunks.  Returns list of CoreMap (Annotation) objects.
  @param tokens - List of tokens to look for chunks
  @param totalTokensOffset - Index of tokens to offset by
  @param textKey - Key to use to find the token text
  @param labelKey - Key to use to find the token label (to determine if inside chunk or not)
  @return List of annotations (each as a CoreMap) representing the chunks of tokens