code: public void setContentType(String photoId, String contentType) throws FlickrException {
          Map<String, Object> parameters = new HashMap<String, Object>();
          parameters.put("method", METHOD_SET_CONTENTTYPE);
  
          parameters.put("photo_id", photoId);
          parameters.put("content_type", contentType);
  
          Response response = transport.post(transport.getPath(), parameters, apiKey, sharedSecret);
          if (response.isError()) {
              throw new FlickrException(response.getErrorCode(), response.getErrorMessage());
          }
      }
docs: Set the content type of a photo.
  
  This method requires authentication with 'write' permission.
  
  @see com.flickr4java.flickr.Flickr#CONTENTTYPE_PHOTO
  @see com.flickr4java.flickr.Flickr#CONTENTTYPE_SCREENSHOT
  @see com.flickr4java.flickr.Flickr#CONTENTTYPE_OTHER
  @param photoId
  The photo ID
  @param contentType
  The contentType to set
  @throws FlickrException