org.apache.pig.newplan.logical.visitor

Class ProjStarInUdfExpander

java.lang.Object

org.apache.pig.newplan.PlanVisitor

org.apache.pig.newplan.logical.relational.LogicalRelationalNodesVisitor

org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor

org.apache.pig.newplan.logical.visitor.ProjStarInUdfExpander

public class ProjStarInUdfExpander
extends AllExpressionVisitor

Expand project-star or project-range when used as udf argument. This is different from ProjectStarExpander because in those cases, the project star gets expanded as new LogicalExpressionPlan. In case of project-star or project-range within udf, it should get expanded only as multiple inputs to this udf, no addtional LogicalExpressionPlans are created. The expansion happens only if input schema is not null

Field Summary

Fields inherited from class org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor

currentOp

Fields inherited from class org.apache.pig.newplan.PlanVisitor

currentWalker, DEFAULT_SCOPE, plan

Constructor Summary

Constructors

Constructor and Description
ProjStarInUdfExpander(OperatorPlan plan)

Method Summary

Methods

Modifier and Type	Method and Description
protected LogicalExpressionVisitor	getVisitor(LogicalExpressionPlan exprPlan) Get a new instance of the expression visitor to apply to a given expression.
void	visit(LOForEach foreach)
void	visit(LOGenerate gen)

Methods inherited from class org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor

visit, visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class org.apache.pig.newplan.logical.relational.LogicalRelationalNodesVisitor

visit, visit, visit, visit, visit, visit, visit, visit

Methods inherited from class org.apache.pig.newplan.PlanVisitor

getPlan, popWalker, pushWalker, visit

Methods inherited from class java.lang.Object

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

Constructor Detail

ProjStarInUdfExpander

public ProjStarInUdfExpander(OperatorPlan plan)
                      throws FrontendException

Throws:

FrontendException

Method Detail

getVisitor

protected LogicalExpressionVisitor getVisitor(LogicalExpressionPlan exprPlan)
                                       throws FrontendException

Description copied from class: AllExpressionVisitor

Get a new instance of the expression visitor to apply to a given expression.

Specified by:

getVisitor in class AllExpressionVisitor

Parameters:

exprPlan - LogicalExpressionPlan that will be visited

Returns:

a new LogicalExpressionVisitor for that expression

Throws:

FrontendException

visit

public void visit(LOForEach foreach)
           throws FrontendException

Overrides:

visit in class AllExpressionVisitor

Throws:

FrontendException

visit

public void visit(LOGenerate gen)
           throws FrontendException

Overrides:

visit in class AllExpressionVisitor

Throws:

FrontendException