@Override
    public RecordCursor cursor()
    {
        return new ExampleRecordCursor(columnHandles, byteSource);
    }
@Test
    public void testCursorSimple()
    {
        RecordSet recordSet = new ExampleRecordSet(new ExampleSplit("test", "schema", "table", dataUri), ImmutableList.of(
                new ExampleColumnHandle("test", "text", createUnboundedVarcharType(), 0),
                new ExampleColumnHandle("test", "value", BIGINT, 1)));
        RecordCursor cursor = recordSet.cursor();

        assertEquals(cursor.getType(0), createUnboundedVarcharType());
        assertEquals(cursor.getType(1), BIGINT);

        Map<String, Long> data = new LinkedHashMap<>();
        while (cursor.advanceNextPosition()) {
            data.put(cursor.getSlice(0).toStringUtf8(), cursor.getLong(1));
            assertFalse(cursor.isNull(0));
            assertFalse(cursor.isNull(1));
        }
        assertEquals(data, ImmutableMap.<String, Long>builder()
                .put("ten", 10L)
                .put("eleven", 11L)
                .put("twelve", 12L)
                .build());
    }