StagePartitioner (Nemo Project 0.4 API)

java.lang.Object
- org.apache.nemo.runtime.common.plan.StagePartitioner

All Implemented Interfaces:

java.util.function.Function<IRDAG,java.util.Map<IRVertex,java.lang.Integer>>
```
@ThreadSafe
public final class StagePartitioner
extends java.lang.Object
implements java.util.function.Function<IRDAG,java.util.Map<IRVertex,java.lang.Integer>>
```
A function that is responsible for stage partitioning on IR DAG. Each stage becomes maximal set of IRVertex such that
- branches and non-OneToOne edges are not allowed within a stage, and
- all vertices in a stage should have same VertexExecutionProperty map, except for the ignored properties.

Constructor Summary

Constructors
Constructor Description

StagePartitioner()

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`addIgnoredPropertyKey(java.lang.Class<? extends VertexExecutionProperty> ignoredPropertyKey)`	By default, the stage partitioner merges two vertices into one stage if and only if the two vertices have same set of `VertexExecutionProperty`.
`java.util.Map<IRVertex,java.lang.Integer>`	`apply(IRDAG irDAG)`
`java.util.Set<VertexExecutionProperty>`	`getStageProperties(IRVertex vertex)`

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

Methods inherited from interface java.util.function.Function
andThen, compose

- Constructor Detail
  - StagePartitioner
```
public StagePartitioner()
```
- Method Detail
  - addIgnoredPropertyKey
```
public void addIgnoredPropertyKey(java.lang.Class<? extends VertexExecutionProperty> ignoredPropertyKey)
```
    By default, the stage partitioner merges two vertices into one stage if and only if the two vertices have same set of VertexExecutionProperty. Invoking this method will make the stage partitioner ignore a specific property during comparing the execution property maps.
    
    Parameters:
    
    ignoredPropertyKey - a property that will be ignored during the stage partitioning.
  - apply
```
public java.util.Map<IRVertex,java.lang.Integer> apply(IRDAG irDAG)
```
    Specified by:
    
    apply in interface java.util.function.Function<IRDAG,java.util.Map<IRVertex,java.lang.Integer>>
    
    Parameters:
    
    irDAG - IR DAG to perform stage partition on.
    
    Returns:
    
    a map between IR vertex and the corresponding stage id
  - getStageProperties
```
public java.util.Set<VertexExecutionProperty> getStageProperties(IRVertex vertex)
```
    Parameters:
    
    vertex - a vertex in a stage
    
    Returns:
    
    set of stage-level properties for the stage