presto-example-http/src/main/java/io/prestosql/plugin/example/ExampleRecordSet.java/ExampleRecordSet/ExampleRecordSet
class ExampleRecordSet:    public ExampleRecordSet(ExampleSplit split, List<ExampleColumnHandle> columnHandles)
    {
        requireNonNull(split, "split is null");

        this.columnHandles = requireNonNull(columnHandles, "column handles is null");
        ImmutableList.Builder<Type> types = ImmutableList.builder();
        for (ExampleColumnHandle column : columnHandles) {
            types.add(column.getColumnType());
        }
        this.columnTypes = types.build();

        try {
            byteSource = Resources.asByteSource(split.getUri().toURL());
        }
        catch (MalformedURLException e) {
            throw new RuntimeException(e);
        }
    }