org.apache.pig.newplan.logical.visitor
Class ColumnAliasConversionVisitor

java.lang.Object
  extended by org.apache.pig.newplan.PlanVisitor
      extended by org.apache.pig.newplan.logical.relational.LogicalRelationalNodesVisitor
          extended by org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor
              extended by org.apache.pig.newplan.logical.visitor.ColumnAliasConversionVisitor

public class ColumnAliasConversionVisitor
extends AllExpressionVisitor

Logical plan visitor which will convert all column alias references to column indexes, using the underlying anonymous expression plan visitor.


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
ColumnAliasConversionVisitor(OperatorPlan plan)
           
 
Method Summary
protected  LogicalExpressionVisitor getVisitor(LogicalExpressionPlan exprPlan)
          Get a new instance of the expression visitor to apply to a given expression.
 
Methods inherited from class org.apache.pig.newplan.logical.optimizer.AllExpressionVisitor
visit, visit, 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

ColumnAliasConversionVisitor

public ColumnAliasConversionVisitor(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


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