code: public DataType getAttributeType(int index) {
          final VertexAttribute attribute = getAttribute(index);
          if (attribute == null) {
              return null;
          }
          return attribute.getType();
      }
docs: Returns the type of the attribute at the provided index, or null if none can be found.
  
  @param index The index to lookup
  @return The type of the attribute, or null if none can be found