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apache-kafkaapache-flinkflink-streamingflink-cep

Creating CEP with Apache Flink


I'm trying to implement a very simple Apache Flink CEP for a Kafka InputStream. The Kafka Producer generates a simple Double Value and send them via a Kafka Topic as String towards the Consumers. At the moment i'm coding a CEP Consumer with Flink. So far this is my written code:

public static void main(String[] args) throws Exception {

        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();
        env.getConfig().disableSysoutLogging();
        env.getConfig().setRestartStrategy(RestartStrategies.fixedDelayRestart(4, 10000)); 
        env.setParallelism(3);
        Properties properties = new Properties();
        properties.setProperty("bootstrap.servers", "localhost:9092");
        properties.setProperty("group.id", "flink_consumer");

        DataStream<String> stream = env
                .addSource(new FlinkKafkaConsumer09<>("temp", new SimpleStringSchema(), properties));

        Pattern<String, ?> warning= Pattern.<String>begin("first")
                .where(new IterativeCondition<String>() {
                    private static final long serialVersionUID = 1L;
                    @Override
                    public boolean filter(String value, Context<String> ctx) throws Exception {
                        return Double.parseDouble(value) >= 89.0;
                    }
                })
                .next("second")
                .where(new IterativeCondition<String>() {
                    private static final long serialVersionUID = 1L;
                    @Override
                    public boolean filter(String value, Context<String> ctx) throws Exception {
                        return Double.parseDouble(value) >= 89.0;
                    }
                })
                .within(Time.seconds(10));  
        DataStream<String> temp = CEP.pattern(stream, warning).select(new PatternSelectFunction<String, String>() {
            private static final long serialVersionUID = 1L;

            @Override
            public String select(Map<String, List<String>> pattern) throws Exception {
                List warnung1 = pattern.get("first");
                String first = (String) warnung1.get(1);
                return first;
            }   

        });

        temp.print();
        env.execute();

    }

if I'm trying to execute this Code this is the error message:

Exception in thread "main" java.lang.NoSuchFieldError: NO_INDEX at org.apache.flink.cep.PatternStream.select(PatternStream.java:102) at CEPTest.main(CEPTest.java:50)

So it looks like my generated DataStream with the CEP Pattern is wrong, but i don't know whats wrong with that method. Every help would be great!

Edit: I tried some other example and at every execution I'm getting the same error. So I think something with my packages is wrong?


Solution

  • With Flink 1.6.0 my code works perfectly.