code: public GeometryEnvelope getOrBuildEnvelope() {
  		GeometryEnvelope envelope = getEnvelope();
  		if (envelope == null) {
  			Geometry geometry = getGeometry();
  			if (geometry != null) {
  				envelope = GeometryEnvelopeBuilder.buildEnvelope(geometry);
  			}
  		}
  		return envelope;
  	}
docs: Get the envelope if it exists or build it from the geometry if not null
  
  @return geometry envelope
  @since 3.1.0