org.apache.pig.backend.hadoop.executionengine.physicalLayer.util

Class PlanHelper

java.lang.Object

org.apache.pig.backend.hadoop.executionengine.physicalLayer.util.PlanHelper

public class PlanHelper
extends Object

Utility class with a few helper functions to deal with physical plans.

Method Summary

Modifier and Type	Method and Description
static <C extends PhysicalOperator> boolean	containsPhysicalOperator(PhysicalPlan plan, Class<C> opClass)
static PhysicalPlan	getLocalRearrangePlanFromSplit(PhysicalPlan plan, OperatorKey rearrangeKey) Finds POLocalRearrange from POSplit sub-plan
static <C> LinkedList<C>	getPhysicalOperators(PhysicalPlan plan, Class<C> opClass) Returns a LinkedList of operators contained within the physical plan which implement the supplied class, in dependency order.
static String	makeStoreTmpPath(String orig) Creates a relative path that can be used to build a temporary place to store the output from a number of map-reduce tasks.

Methods inherited from class java.lang.Object

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

Method Detail

makeStoreTmpPath

public static String makeStoreTmpPath(String orig)

Creates a relative path that can be used to build a temporary place to store the output from a number of map-reduce tasks.

containsPhysicalOperator

public static <C extends PhysicalOperator> boolean containsPhysicalOperator(PhysicalPlan plan,
                                                                            Class<C> opClass)
                                                                     throws VisitorException

Throws:

VisitorException

getPhysicalOperators

public static <C> LinkedList<C> getPhysicalOperators(PhysicalPlan plan,
                                                     Class<C> opClass)
                                              throws VisitorException

Returns a LinkedList of operators contained within the physical plan which implement the supplied class, in dependency order. Returns an empty LinkedList of no such operators exist.

Parameters:

plan -

opClass -

Returns:

a LinkedList of operators contained within the plan which implement the supplied class; empty if no such ops exist.

Throws:

VisitorException

getLocalRearrangePlanFromSplit

public static PhysicalPlan getLocalRearrangePlanFromSplit(PhysicalPlan plan,
                                                          OperatorKey rearrangeKey)
                                                   throws VisitorException

Finds POLocalRearrange from POSplit sub-plan

Parameters:

plan - physical plan

rearrangeKey - operator key of the POLocalRearrange

Returns:

POLocalRearrange with the specified operator key which is in a sub-plan of POSplit

Throws:

VisitorException