org.apache.flink.cep

Interface PatternTimeoutFunction<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

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

Base interface for a pattern timeout function. A pattern timeout function is called with a map containing the timed out partial events which can be accessed by their names and the timestamp when the timeout occurred. The names depend on the definition of the Pattern. The timeout method returns exactly one result. If you want to return more than one result, then you have to implement a PatternFlatTimeoutFunction.

 PatternStream<IN> pattern = ...;

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

Method Summary

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

Method Detail

timeout

OUT timeout(Map<String,List<IN>> pattern,
            long timeoutTimestamp)
     throws Exception

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

Parameters:

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

timeoutTimestamp - Timestamp of the timeout

Returns:

Resulting timeout element

Throws:

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