PartitionMapper (Jakarta EE Platform API)

```
public interface PartitionMapper
```
PartitionMapper receives control at the start of a partitioned execution. A PartitionMapper is responsible to provide unique batch properties for each partition.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`PartitionPlan`	`mapPartitions()`	The mapPartitions method that receives control at the start of partitioned step processing.

- Method Detail
  - mapPartitions
```
PartitionPlan mapPartitions()
                     throws Exception
```
    The mapPartitions method that receives control at the start of partitioned step processing. The method returns a PartitionPlan, which specifies the batch properties for each partition.
    
    Returns:
    
    partition plan for a partitioned step.
    
    Throws:
    
    Exception - is thrown if an error occurs.