org.apache.pig.newplan.logical.expression
Class ScalarExpression
java.lang.Object
org.apache.pig.newplan.Operator
org.apache.pig.newplan.logical.expression.LogicalExpression
org.apache.pig.newplan.logical.expression.UserFuncExpression
org.apache.pig.newplan.logical.expression.ScalarExpression
public class ScalarExpression
- extends UserFuncExpression
ScalarExpression
public ScalarExpression(OperatorPlan plan)
ScalarExpression
public ScalarExpression(OperatorPlan plan,
Operator implicitReferencedOperator,
Operator attachedLogicalOperator)
getFieldSchema
public LogicalSchema.LogicalFieldSchema getFieldSchema()
throws FrontendException
- Description copied from class:
LogicalExpression
- Get the field schema for the output of this expression operator. This does
not merely return the field schema variable. If schema is not yet set, this
will attempt to construct it. Therefore it is abstract since each
operator will need to construct its field schema differently.
- Overrides:
getFieldSchema
in class UserFuncExpression
- Returns:
- the FieldSchema
- Throws:
FrontendException
deepCopy
public LogicalExpression deepCopy(LogicalExpressionPlan lgExpPlan)
throws FrontendException
- Description copied from class:
LogicalExpression
- Create the deep copy of this expression and add that into the passed
LogicalExpressionPlan Return the copy of this expression with updated
logical expression plan.
- Overrides:
deepCopy
in class UserFuncExpression
- Parameters:
lgExpPlan
- LogicalExpressionPlan in which this expression will be added.
- Returns:
- LogicalExpression with its own logical expression plan.
- Throws:
FrontendException
accept
public void accept(PlanVisitor v)
throws FrontendException
- Description copied from class:
Operator
- Accept a visitor at this node in the graph.
- Overrides:
accept
in class UserFuncExpression
- Parameters:
v
- Visitor to accept.
- Throws:
FrontendException
getImplicitReferencedOperator
public Operator getImplicitReferencedOperator()
setImplicitReferencedOperator
public void setImplicitReferencedOperator(Operator implicitReferencedOperator)
setAttachedLogicalOperator
public void setAttachedLogicalOperator(Operator attachedLogicalOperator)
getAttachedLogicalOperator
public Operator getAttachedLogicalOperator()
toString
public String toString()
- Overrides:
toString
in class UserFuncExpression
Copyright © 2012 The Apache Software Foundation