presto-thrift/src/main/java/io/prestosql/plugin/thrift/ThriftSplitManager.java/ThriftSplitManager/columnNames
class ThriftSplitManager:    private static Set<String> columnNames(Set<ColumnHandle> columns)
    {
        return columns.stream()
                .map(ThriftColumnHandle.class::cast)
                .map(ThriftColumnHandle::getColumnName)
                .collect(toImmutableSet());
    }