Github user dianfu commented on a diff in the pull request: https://github.com/apache/flink/pull/4296#discussion_r135440842 --- Diff: flink-libraries/flink-cep/src/main/java/org/apache/flink/cep/nfa/compiler/NFACompiler.java --- @@ -526,18 +551,32 @@ private boolean isPatternOptional(Pattern<T, ?> pattern) { return createGroupPatternState((GroupPattern) currentPattern, sinkState, proceedState, isOptional); } - final IterativeCondition<T> trueFunction = getTrueFunction(); - final State<T> singletonState = createState(currentPattern.getName(), State.StateType.Normal); // if event is accepted then all notPatterns previous to the optional states are no longer valid final State<T> sink = copyWithoutTransitiveNots(sinkState); singletonState.addTake(sink, takeCondition); + // if no element accepted the previous nots are still valid. + final IterativeCondition<T> proceedCondition = getTrueFunction(); + // for the first state of a group pattern, its PROCEED edge should point to the following state of // that group pattern and the edge will be added at the end of creating the NFA for that group pattern if (isOptional && !headOfGroup(currentPattern)) { - // if no element accepted the previous nots are still valid. - singletonState.addProceed(proceedState, trueFunction); + if (currentPattern.getQuantifier().hasProperty(Quantifier.QuantifierProperty.GREEDY)) { + final IterativeCondition<T> untilCondition = + (IterativeCondition<T>) currentPattern.getUntilCondition(); + if (untilCondition != null) { + singletonState.addProceed( + originalStateMap.get(proceedState.getName()), + new AndCondition<>(proceedCondition, untilCondition)); --- End diff -- When untilCondition holds, the loop should break and the state should proceed to the next state. This is covered by the test case GreedyITCase#testGreedyUntilWithDummyEventsBeforeQuantifier.
--- If your project is set up for it, you can reply to this email and have your reply appear on GitHub as well. If your project does not have this feature enabled and wishes so, or if the feature is enabled but not working, please contact infrastructure at infrastruct...@apache.org or file a JIRA ticket with INFRA. ---