org.apache.flink.cep

Interface PatternSelectFunction<IN,OUT>

Type Parameters:

IN - Type of the input elements

OUT - Type of the output element

All Superinterfaces:

org.apache.flink.api.common.functions.Function, Serializable

All Known Implementing Classes:

RichPatternSelectFunction

public interface PatternSelectFunction<IN,OUT>
extends org.apache.flink.api.common.functions.Function, Serializable

Base interface for a pattern select function. A pattern select function is called with a map containing the detected events which can be accessed by their names. The names depend on the definition of the Pattern. The select method returns exactly one result. If you want to return more than one result, then you have to implement a PatternFlatSelectFunction.

 PatternStream<IN> pattern = ...;

 DataStream<OUT> result = pattern.select(new MyPatternSelectFunction());
 

Method Summary

Modifier and Type	Method and Description
OUT	select(Map<String,List<IN>> pattern) Generates a result from the given map of events.

Method Detail

select

OUT select(Map<String,List<IN>> pattern)
    throws Exception

Generates a result from the given map of events. The events are identified by their names. Only one resulting element can be generated.

Parameters:

pattern - Map containing the found pattern. Events are identified by their names

Returns:

Resulting element

Throws:

Exception - This method may throw exceptions. Throwing an exception will cause the operation to fail and may trigger recovery.