Question

Pattern< Tuple3< String, String, String >, ? > pattern = Pattern.<Tuple3< String, String, String > > begin( "start" )            
            .next( "3" ).where( new FilterFunction< Tuple3< String, String, String > >() {
                @Override
                public boolean filter ( Tuple3< String, String, String > value ) throws Exception {
                    return value.f2.equals( "3" );
                }
            } )
            .next( "4" ).subtype(Tuple.getTupleClass( 2 )).where( new FilterFunction< Tuple2< String, String> >() {
                @Override
                public boolean filter ( Tuple2< String, String > value ) throws Exception {
                    return value.f1.equals( "3" );
                }
            } )

子类型（Tuple.getTupleClass（2）），并显示错误 Inferred type 'capture<? extends org.apapche.flink.api.java.tuple.Tuple>' for type parameter 'S' is not within its bound;should extend 'org.apapche.flink.api.java.tuple.Tuple3<java.lang.String,java.lang.String,java.lang.String>'

我应该修改吗？但是如何修改？Pattern< Tuple3< String, String, String >, ? > pattern

到2017012更新

JoinedStreams< Tuple2< String, String >, Tuple3< String, String, String > >.Where< String >.EqualTo
        joinedStreams = someStream
        .join( otherStream )
        .where( value -> value.f1 )
        .equalTo( value -> value.f1 );

Pattern< Tuple, ? > pattern = Pattern.< Tuple > begin( "start" )
        .subtype( Tuple3.class )
        .where( evt -> evt.f2.equals( "3" ) )
        .next( "4" )
        .subtype( Tuple2.class )
        .where( evt -> evt.f1.equals( "3" ) )
        .within( Time.seconds( 10 ) );

PatternStream< ...> patternStream = CEP.pattern( joinedStreams, pattern );

我试过这个，并且不应该填写PatternStream< ...>。感谢任何可以提供帮助的人。

Answer 1

试试这段代码：

Pattern<Tuple, ?> pattern =
    Pattern.<Tuple>begin("start")
    .next("3")
        .subtype(Tuple3.class)
        .where(new FilterFunction<Tuple3>() {

            @Override
            public boolean filter(Tuple3 value) throws Exception {
                return value.f2.equals("3");
            }
        })
    .next("4")
        .subtype(Tuple2.class)
        .where(new FilterFunction<Tuple2>() {

            @Override
            public boolean filter(Tuple2 value) throws Exception {
                return value.f1.equals("3");
            }
        });

从公共类型Tuple开始，并为子事件使用具体类型Tuple2和Tuple3。此模式的数据流必须具有Tuple类型。

Answer 2

怎么样：

    Pattern<Tuple, ?> pattern = Pattern.<Tuple>begin("start")
            .subtype(Tuple3.class)
            .where(evt -> evt.f2.equals("3"))
            .next("4")
            .subtype(Tuple2.class)
            .where(evt -> evt.f1.equals("3"))
            .within(Time.seconds(10));

开始后不需要添加下一个
注意子类型的字面含义，tuple3和tuple2应该扩展元组。

如果要连接两个不同的数据流。

DataStream<Tuple2> someStream = //...
DataStream<Tuple3> otherStream = //...

ConnectedStreams<Tuple2, Tuple3> connectedStreams = someStream.connect(otherStream);

然后你可以使用CoMap，CoFlatMap来获得相同的类型，例如将Tuple2，Tuple3转换为String： ConnectedStreams→DataStream

connectedStreams.flatMap(new CoFlatMapFunction<Tuple2, Tuple3, String>() {

   @Override
   public void flatMap1(Integer value, Collector<String> out) {
       out.collect(Tuple2.toString());
   }

   @Override
   public void flatMap2(String value, Collector<String> out) {
       for (String word: value.split(" ")) {
         out.collect(Tuple3.toString);
       }
   }
});

以下是一些有用的链接，介绍了一个很好的用例：

如何在flink cep中做subtype（）to tuple？

2 个答案: