org.apache.flink.streaming.python.api.functions

Class PythonMapFunction

java.lang.Object

org.apache.flink.api.common.functions.AbstractRichFunction

org.apache.flink.streaming.python.api.functions.AbstractPythonUDF<MapFunction<org.python.core.PyObject,org.python.core.PyObject>>

org.apache.flink.streaming.python.api.functions.PythonMapFunction

All Implemented Interfaces:

Serializable, Function, MapFunction<org.python.core.PyObject,org.python.core.PyObject>, RichFunction

public class PythonMapFunction
extends AbstractPythonUDF<MapFunction<org.python.core.PyObject,org.python.core.PyObject>>
implements MapFunction<org.python.core.PyObject,org.python.core.PyObject>

The PythonMapFunction is a thin wrapper layer over a Python UDF MapFunction. It receives a MapFunction as an input and keeps it internally in a serialized form. It is then delivered, as part of the job graph, up to the TaskManager, then it is opened and becomes a sort of mediator to the Python UDF MapFunction.

This function is used internally by the Python thin wrapper layer over the streaming data functionality

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.flink.streaming.python.api.functions.AbstractPythonUDF

fun, log

Constructor Summary

Constructors

Constructor and Description
PythonMapFunction(MapFunction<org.python.core.PyObject,org.python.core.PyObject> fun)

Method Summary

Modifier and Type	Method and Description
org.python.core.PyObject	map(org.python.core.PyObject value) The mapping method.

Methods inherited from class org.apache.flink.streaming.python.api.functions.AbstractPythonUDF

close, open

Methods inherited from class org.apache.flink.api.common.functions.AbstractRichFunction

getIterationRuntimeContext, getRuntimeContext, setRuntimeContext

Methods inherited from class java.lang.Object

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

Constructor Detail

PythonMapFunction

public PythonMapFunction(MapFunction<org.python.core.PyObject,org.python.core.PyObject> fun)
                  throws IOException

Throws:

IOException

Method Detail

map

public org.python.core.PyObject map(org.python.core.PyObject value)
                             throws Exception

Description copied from interface: MapFunction

The mapping method. Takes an element from the input data set and transforms it into exactly one element.

Specified by:

map in interface MapFunction<org.python.core.PyObject,org.python.core.PyObject>

Parameters:

value - The input value.

Returns:

The transformed value

Throws:

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