org.apache.flink.compiler.plantranslate

Class NepheleJobGraphGenerator

java.lang.Object

org.apache.flink.compiler.plantranslate.NepheleJobGraphGenerator

All Implemented Interfaces:

Visitor<PlanNode>

public class NepheleJobGraphGenerator
extends Object
implements Visitor<PlanNode>

This component translates the optimizer's resulting plan a nephele job graph. The translation is a one to one mapping. All decisions are made by the optimizer, this class simply creates nephele data structures and descriptions corresponding to the optimizer's result.

The basic method of operation is a top down traversal over the plan graph. On the way down, tasks are created for the plan nodes, on the way back up, the nodes connect their predecessor.

Field Summary

Fields

Modifier and Type	Field and Description
static String	MERGE_ITERATION_AUX_TASKS_KEY

Constructor Summary

Constructors

Constructor and Description
NepheleJobGraphGenerator() Creates a new job graph generator that uses the default values for its resource configuration.
NepheleJobGraphGenerator(Configuration config)

Method Summary

Modifier and Type	Method and Description
JobGraph	compileJobGraph(OptimizedPlan program) Translates a OptimizedPlan into a JobGraph.
void	postVisit(PlanNode node) This method implements the post-visit during the depth-first traversal.
boolean	preVisit(PlanNode node) This methods implements the pre-visiting during a depth-first traversal.

Methods inherited from class java.lang.Object

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

Field Detail

MERGE_ITERATION_AUX_TASKS_KEY

public static final String MERGE_ITERATION_AUX_TASKS_KEY

See Also:

Constant Field Values

Constructor Detail

NepheleJobGraphGenerator

public NepheleJobGraphGenerator()

Creates a new job graph generator that uses the default values for its resource configuration.

NepheleJobGraphGenerator

public NepheleJobGraphGenerator(Configuration config)

Method Detail

compileJobGraph

public JobGraph compileJobGraph(OptimizedPlan program)

Translates a OptimizedPlan into a JobGraph. This is an 1-to-1 mapping. No optimization whatsoever is applied.

Parameters:

program - Optimized PACT plan that is translated into a JobGraph.

Returns:

JobGraph generated from PACT plan.

preVisit

public boolean preVisit(PlanNode node)

This methods implements the pre-visiting during a depth-first traversal. It create the job vertex and sets local strategy.

Specified by:

preVisit in interface Visitor<PlanNode>

Parameters:

node - The node that is currently processed.

Returns:

True, if the visitor should descend to the node's children, false if not.

See Also:

Visitor.preVisit(org.apache.flink.util.Visitable)

postVisit

public void postVisit(PlanNode node)

This method implements the post-visit during the depth-first traversal. When the post visit happens, all of the descendants have been processed, so this method connects all of the current node's predecessors to the current node.

Specified by:

postVisit in interface Visitor<PlanNode>

Parameters:

node - The node currently processed during the post-visit.

See Also:

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