in2.add(ex2);
ex2.setStringAsString("d");
ex2.setSid(6);
in2.add(ex2);
assertThat(tester.runFlow(new MasterJoinFlowSelection(
in1.flow(), in2.flow(),
joined.flow(), missing.flow())), is(true));
List<ExJoined> joinedList = joined.toList(new Comparator<ExJoined>() {
@Override