ModelConverterUtils { static void appendMetaRow(Params meta, Collector<Row> collector, final int numFields) { if (meta != null) { appendStringData(meta.toJson(), collector, numFields, 0); } }    }
@Test public void testAppendMetaRow() throws Exception { Params meta = new Params().set(SOME_PARAM, "value"); MockCollector collector = new MockCollector(); ModelConverterUtils.appendMetaRow(meta, collector, 2); Row row = collector.buffer.get(0); Assert.assertEquals(row.getArity(), 2); Assert.assertEquals(row.getField(0), 0L); Assert.assertEquals(row.getField(1), meta.toJson()); }