in flume-morphline-solr-sink/src/main/java/org/apache/flume/sink/solr/morphline/MorphlineInterceptor.java [159:172]
public Event intercept(Event event) {
collector.reset();
morphline.process(event);
List<Record> results = collector.getRecords();
if (results.size() == 0) {
return null;
}
if (results.size() > 1) {
throw new FlumeException(getClass().getName() +
" must not generate more than one output record per input event");
}
Event result = toEvent(results.get(0));
return result;
}