presto-hive/src/main/java/io/prestosql/plugin/hive/metastore/RecordingHiveMetastore.java/RecordingHiveMetastore/toMap
class RecordingHiveMetastore:    private static <K, V> Map<K, V> toMap(List<Pair<K, V>> pairs)
    {
        return pairs.stream()
                .collect(ImmutableMap.toImmutableMap(Pair::getKey, Pair::getValue));
    }