@Override
        public void run() {
            // consume new data
            for (Data newData : incomingData.drain()) {
                incomingData.getOwner().add(newData);
            }
            // actual rendering would go here (at this point data add listeners will have executed)
        }
Tests adding a chain which is called every time new data is added to a data list
container-core/src/test/java/com/yahoo/processing/execution/test/StreamingTestCase.java