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

All Implemented Interfaces:

java.io.Serializable

public class ScalarExpression
extends UserFuncExpression

See Also:

Serialized Form

Field Summary

Fields inherited from class org.apache.pig.newplan.logical.expression.LogicalExpression

fieldSchema, uidOnlyFieldSchema

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

annotations, hashPrime, location, name, plan

Constructor Summary

Constructors

Constructor and Description
ScalarExpression(OperatorPlan plan)
ScalarExpression(OperatorPlan plan, Operator implicitReferencedOperator, Operator attachedLogicalOperator)

Method Summary

Modifier and Type	Method and Description
void	accept(PlanVisitor v) Accept a visitor at this node in the graph.
LogicalExpression	deepCopy(LogicalExpressionPlan lgExpPlan) 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.
Operator	getAttachedLogicalOperator()
LogicalSchema.LogicalFieldSchema	getFieldSchema() Get the field schema for the output of this expression operator.
Operator	getImplicitReferencedOperator()
void	setAttachedLogicalOperator(Operator attachedLogicalOperator)
void	setImplicitReferencedOperator(Operator implicitReferencedOperator)
java.lang.String	toString()

Methods inherited from class org.apache.pig.newplan.logical.expression.UserFuncExpression

getArguments, getEvalFunc, getFuncSpec, getSignature, isDeterministic, isEqual, isViaDefine, setFuncSpec

Methods inherited from class org.apache.pig.newplan.logical.expression.LogicalExpression

getNextUid, getType, hasFieldSchema, neverUseForRealSetFieldSchema, resetFieldSchema, resetNextUid, resetUid

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

annotate, getAnnotation, getLocation, getName, getPlan, removeAnnotation, setLocation, setPlan

Methods inherited from class java.lang.Object

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

Constructor Detail

ScalarExpression

public ScalarExpression(OperatorPlan plan)

ScalarExpression

public ScalarExpression(OperatorPlan plan,
                        Operator implicitReferencedOperator,
                        Operator attachedLogicalOperator)

Method Detail

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 java.lang.String toString()

Overrides:

toString in class UserFuncExpression