code: public long count(GeometryEnvelope envelope) {
  		long count = 0;
  
  		QueryBuilder<GeometryIndex, GeometryIndexKey> qb = queryBuilder(envelope);
  		try {
  			count = qb.countOf();
  		} catch (SQLException e) {
  			throw new GeoPackageException(
  					"Failed to query for Geometry Index count. GeoPackage: "
  							+ geoPackage.getName() + ", Table Name: "
  							+ tableName + ", Column Name: " + columnName, e);
  		}
  
  		return count;
  	}
docs: Query for Geometry Index count within the Geometry Envelope
  
  @param envelope
  geometry envelope
  @return count