@Override
    public void finish()
            throws IOException
    {
        writer.flush();
    }
@Test
    public void testJsonPrintingNoRows()
            throws Exception
    {
        StringWriter writer = new StringWriter();
        List<String> fieldNames = ImmutableList.of("first", "last");
        OutputPrinter printer = new JsonPrinter(fieldNames, writer);

        printer.finish();

        assertEquals(writer.getBuffer().toString(), "");
    }