Package org.apache.flink.table.runtime.operators.match

Class IterativeConditionRunner

java.lang.Object

org.apache.flink.cep.pattern.conditions.IterativeCondition<T>

org.apache.flink.cep.pattern.conditions.RichIterativeCondition<RowData>

org.apache.flink.table.runtime.operators.match.IterativeConditionRunner

All Implemented Interfaces:

Serializable, Function, RichFunction

public class IterativeConditionRunner
extends RichIterativeCondition<RowData>

A RichIterativeCondition wrapper to delegate invocation to the code generated RichIterativeCondition.

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.flink.cep.pattern.conditions.IterativeCondition

IterativeCondition.Context<T>

Constructor Summary

Constructors

Constructor	Description
IterativeConditionRunner(GeneratedFunction<RichIterativeCondition<RowData>> generatedFunction)

Method Summary

Modifier and Type	Method	Description
void	close()	Tear-down method for the user code.
boolean	filter(RowData value, IterativeCondition.Context<RowData> ctx)	The filter function that evaluates the predicate.
void	open(OpenContext openContext)	Initialization method for the function.

Methods inherited from class org.apache.flink.cep.pattern.conditions.RichIterativeCondition

getIterationRuntimeContext, getRuntimeContext, setRuntimeContext

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

IterativeConditionRunner

public IterativeConditionRunner(GeneratedFunction<RichIterativeCondition<RowData>> generatedFunction)

Method Detail

open

public void open(OpenContext openContext)
          throws Exception

Description copied from interface: RichFunction

Initialization method for the function. It is called before the actual working methods (like map or join) and thus suitable for one time setup work. For functions that are part of an iteration, this method will be invoked at the beginning of each iteration superstep.

The openContext object passed to the function can be used for configuration and initialization. The openContext contains some necessary information that were configured on the function in the program composition.

 public class MyFilter extends RichFilterFunction<String> {

     private String searchString;

     public void open(OpenContext openContext) {
         // initialize the value of searchString
     }

     public boolean filter(String value) {
         return value.equals(searchString);
     }
 }
 

Specified by:

open in interface RichFunction

Overrides:

open in class RichIterativeCondition<RowData>

Parameters:

openContext - The context containing information about the context in which the function is opened.

Throws:

Exception - Implementations may forward exceptions, which are caught by the runtime. When the runtime catches an exception, it aborts the task and lets the fail-over logic decide whether to retry the task execution.

filter

public boolean filter(RowData value,
                      IterativeCondition.Context<RowData> ctx)
               throws Exception

Description copied from class: IterativeCondition

The filter function that evaluates the predicate.

IMPORTANT: The system assumes that the function does not modify the elements on which the predicate is applied. Violating this assumption can lead to incorrect results.

Specified by:

filter in class IterativeCondition<RowData>

Parameters:

value - The value to be tested.

ctx - The IterativeCondition.Context used for the evaluation of the function and provides access to the already accepted events in the pattern (see IterativeCondition.Context.getEventsForPattern(String)).

Returns:

true for values that should be retained, false for values to be filtered out.

Throws:

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

close

public void close()
           throws Exception

Description copied from interface: RichFunction

Tear-down method for the user code. It is called after the last call to the main working methods (e.g. map or join). For functions that are part of an iteration, this method will be invoked after each iteration superstep.

This method can be used for clean up work.

Specified by:

close in interface RichFunction

Overrides:

close in class RichIterativeCondition<RowData>

Throws:

Exception - Implementations may forward exceptions, which are caught by the runtime. When the runtime catches an exception, it aborts the task and lets the fail-over logic decide whether to retry the task execution.