public List<Comment> getComments() throws Exception {
if(comments == null) {
HashMap<String, Object> map = new HashMap<String, Object>();
map.put("media_id", getId());
String uri = uriConstructor.constructUri(UriFactory.Comments.GET_MEDIA_COMMENTS, map, true);
JSONObject object = (new GetMethod(uri)).call().getJSON();
JSONArray commentObjects = object.getJSONArray("data");
ArrayList<Comment> comments = new ArrayList<Comment>();
for(int i = 0; i < commentObjects.length(); i++) {
comments.add(new Comment(commentObjects.getJSONObject(i), accessToken));
}