code: public void extractFieldTypes(DatabaseType databaseType) throws SQLException {
  		if (fieldTypes == null) {
  			if (fieldConfigs == null) {
  				fieldTypes = extractFieldTypes(databaseType, dataClass, tableName);
  			} else {
  				fieldTypes = convertFieldConfigs(databaseType, tableName, fieldConfigs);
  			}
  		}
  	}
docs: Extract the field types from the fieldConfigs if they have not already been configured.