How to use

getStates

method

in

org.apache.flink.cep.nfa.compiler.NFACompiler$NFAFactoryCompiler

NFAFactoryCompiler<?> compiler = new NFAFactoryCompiler<>(checkNotNull(pattern));
compiler.compileFactory();
State<?> startState = compiler.getStates().stream().filter(State::isStart).findFirst().orElseThrow(
  () -> new IllegalStateException("Compiler produced no start state. It is a bug. File a jira."));

/**
 * Compiles the given pattern into a {@link NFAFactory}. The NFA factory can be used to create
 * multiple NFAs.
 *
 * @param pattern Definition of sequence pattern
 * @param timeoutHandling True if the NFA shall return timed out event patterns
 * @param <T> Type of the input events
 * @return Factory for NFAs corresponding to the given pattern
 */
@SuppressWarnings("unchecked")
public static <T> NFAFactory<T> compileFactory(
  final Pattern<T, ?> pattern,
  boolean timeoutHandling) {
  if (pattern == null) {
    // return a factory for empty NFAs
    return new NFAFactoryImpl<>(0, Collections.<State<T>>emptyList(), timeoutHandling);
  } else {
    final NFAFactoryCompiler<T> nfaFactoryCompiler = new NFAFactoryCompiler<>(pattern);
    nfaFactoryCompiler.compileFactory();
    return new NFAFactoryImpl<>(nfaFactoryCompiler.getWindowTime(), nfaFactoryCompiler.getStates(), timeoutHandling);
  }
}

@Test
public void testNoUnnecessaryStateCopiesCreated() {
  final Pattern<Event, Event> pattern = Pattern.<Event>begin("start").where(startFilter)
    .notFollowedBy("not").where(startFilter)
    .followedBy("oneOrMore").where(startFilter).oneOrMore()
    .followedBy("end").where(endFilter);
  final NFACompiler.NFAFactoryCompiler<Event> nfaFactoryCompiler = new NFACompiler.NFAFactoryCompiler<>(pattern);
  nfaFactoryCompiler.compileFactory();
  int endStateCount = 0;
  for (State<Event> state : nfaFactoryCompiler.getStates()) {
    if (state.getName().equals("end")) {
      endStateCount++;
    }
  }
  assertEquals(1, endStateCount);
}

/**
 * Compiles the given pattern into a {@link NFAFactory}. The NFA factory can be used to create
 * multiple NFAs.
 *
 * @param pattern Definition of sequence pattern
 * @param timeoutHandling True if the NFA shall return timed out event patterns
 * @param <T> Type of the input events
 * @return Factory for NFAs corresponding to the given pattern
 */
@SuppressWarnings("unchecked")
public static <T> NFAFactory<T> compileFactory(
  final Pattern<T, ?> pattern,
  boolean timeoutHandling) {
  if (pattern == null) {
    // return a factory for empty NFAs
    return new NFAFactoryImpl<>(0, Collections.<State<T>>emptyList(), timeoutHandling);
  } else {
    final NFAFactoryCompiler<T> nfaFactoryCompiler = new NFAFactoryCompiler<>(pattern);
    nfaFactoryCompiler.compileFactory();
    return new NFAFactoryImpl<>(nfaFactoryCompiler.getWindowTime(), nfaFactoryCompiler.getStates(), timeoutHandling);
  }
}

/**
 * Compiles the given pattern into a {@link NFAFactory}. The NFA factory can be used to create
 * multiple NFAs.
 *
 * @param pattern Definition of sequence pattern
 * @param timeoutHandling True if the NFA shall return timed out event patterns
 * @param <T> Type of the input events
 * @return Factory for NFAs corresponding to the given pattern
 */
@SuppressWarnings("unchecked")
public static <T> NFAFactory<T> compileFactory(
  final Pattern<T, ?> pattern,
  boolean timeoutHandling) {
  if (pattern == null) {
    // return a factory for empty NFAs
    return new NFAFactoryImpl<>(0, Collections.<State<T>>emptyList(), timeoutHandling);
  } else {
    final NFAFactoryCompiler<T> nfaFactoryCompiler = new NFAFactoryCompiler<>(pattern);
    nfaFactoryCompiler.compileFactory();
    return new NFAFactoryImpl<>(nfaFactoryCompiler.getWindowTime(), nfaFactoryCompiler.getStates(), timeoutHandling);
  }
}

/**
 * Compiles the given pattern into a {@link NFAFactory}. The NFA factory can be used to create
 * multiple NFAs.
 *
 * @param pattern Definition of sequence pattern
 * @param inputTypeSerializer Serializer for the input type
 * @param timeoutHandling True if the NFA shall return timed out event patterns
 * @param <T> Type of the input events
 * @return Factory for NFAs corresponding to the given pattern
 */
@SuppressWarnings("unchecked")
public static <T> NFAFactory<T> compileFactory(
  final Pattern<T, ?> pattern,
  final TypeSerializer<T> inputTypeSerializer,
  boolean timeoutHandling) {
  if (pattern == null) {
    // return a factory for empty NFAs
    return new NFAFactoryImpl<>(inputTypeSerializer, 0, Collections.<State<T>>emptyList(), timeoutHandling);
  } else {
    final NFAFactoryCompiler<T> nfaFactoryCompiler = new NFAFactoryCompiler<>(pattern);
    nfaFactoryCompiler.compileFactory();
    return new NFAFactoryImpl<>(inputTypeSerializer, nfaFactoryCompiler.getWindowTime(), nfaFactoryCompiler.getStates(), timeoutHandling);
  }
}

NFAFactoryCompiler<?> compiler = new NFAFactoryCompiler<>(checkNotNull(pattern));
compiler.compileFactory();
State<?> startState = compiler.getStates().stream().filter(State::isStart).findFirst().orElseThrow(
  () -> new IllegalStateException("Compiler produced no start state. It is a bug. File a jira."));

NFAFactoryCompiler<?> compiler = new NFAFactoryCompiler<>(checkNotNull(pattern));
compiler.compileFactory();
State<?> startState = compiler.getStates().stream().filter(State::isStart).findFirst().orElseThrow(
  () -> new IllegalStateException("Compiler produced no start state. It is a bug. File a jira."));