@Internal public class PartitionCustomKeySelector extends Object implements KeySelector<Row,Integer>
PartitionCustomKeySelector
will return the first field of the input row value. The
input value is generated by the PythonPartitionCustomOperator
after executed user defined
partitioner and keySelector function. The value of the first field will be the desired partition
index.Constructor and Description |
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PartitionCustomKeySelector() |
Modifier and Type | Method and Description |
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Integer |
getKey(Row value)
User-defined function that deterministically extracts the key from an object.
|
public Integer getKey(Row value) throws Exception
KeySelector
For example for a class:
public class Word { String word; int count; }
The key extractor could return the word as a key to group all Word objects by the String they contain.
The code would look like this
public String getKey(Word w) { return w.word; }
getKey
in interface KeySelector<Row,Integer>
value
- The object to get the key from.Exception
- Throwing an exception will cause the execution of the respective task to
fail, and trigger recovery or cancellation of the program.Copyright © 2014–2021 The Apache Software Foundation. All rights reserved.