public static List<String> getPvals(List<FieldSchema> partCols,
                                      Map<String, String> partSpec) {
    List<String> pvals = new ArrayList<>(partCols.size());
    for (FieldSchema field : partCols) {
      String val = StringUtils.defaultString(partSpec.get(field.getName()));
      pvals.add(val);
    }
    return pvals;
  }
Given a list of partition columns and a partial mapping from
some partition columns to values the function returns the values
for the column.
@param partCols the list of table partition columns
@param partSpec the partial mapping from partition column to values
@return list of values of for given partition columns, any missing
        values in partSpec is replaced by an empty string
standalone-metastore/metastore-common/src/main/java/org/apache/hadoop/hive/metastore/utils/MetaStoreUtils.java