@Test
public void testChild() throws RecognitionException {

  CommonTree sink = FlumeBuilder.parseSink(simple);
  PatternMatch pp = kind("DECO").child(
      kind("SINK").child(var("node", kind("batch"))));
  Map<String, CommonTree> m = pp.match(sink);
  assertNotNull(m);
  dumpMatches(m);
  LOG.info(m);
}