DedicatedKeyPerElementPartitioner (Nemo Project 0.4 API)

java.lang.Object
- org.apache.nemo.common.partitioner.DedicatedKeyPerElementPartitioner

All Implemented Interfaces:

Partitioner<java.lang.Integer>
```
@DedicatedKeyPerElement
public final class DedicatedKeyPerElementPartitioner
extends java.lang.Object
implements Partitioner<java.lang.Integer>
```
An implementation of Partitioner which assigns a dedicated key per an output data from a task. WARNING: Because this partitioner assigns a dedicated key per element, it should be used under specific circumstances that the number of output element is not that many. For example, every output element of StreamTransform inserted by large shuffle optimization is always a partition. In this case, assigning a key for each element can be useful.

Constructor Summary

Constructors
Constructor Description

DedicatedKeyPerElementPartitioner()
Constructor.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`java.lang.Integer`	`partition(java.lang.Object element)`	Divides the output data from a task into multiple blocks.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - DedicatedKeyPerElementPartitioner
```
public DedicatedKeyPerElementPartitioner()
```
    Constructor.
- Method Detail
  - partition
```
public java.lang.Integer partition(java.lang.Object element)
```
    Description copied from interface: Partitioner
    
    Divides the output data from a task into multiple blocks.
    
    Specified by:
    
    partition in interface Partitioner<java.lang.Integer>
    
    Parameters:
    
    element - the output element from a source task.
    
    Returns:
    
    the key of the partition in the block to write the element.