org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators
Class ConstantExpression

java.lang.Object
  extended by org.apache.pig.impl.plan.Operator<PhyPlanVisitor>
      extended by org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator
          extended by org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.ExpressionOperator
              extended by org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.ConstantExpression
All Implemented Interfaces:
Serializable, Cloneable, Comparable<Operator>, Illustrable

public class ConstantExpression
extends ExpressionOperator

This class implements a Constant of any type. Its value can be set using the setValue method.

See Also:
Serialized Form

Nested Class Summary
 
Nested classes/interfaces inherited from class org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator
PhysicalOperator.OriginalLocation
 
Field Summary
 
Fields inherited from class org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator
alias, illustrator, input, inputAttached, inputs, lineageTracer, outputs, parentPlan, pigLogger, requestedParallelism, resultType
 
Fields inherited from class org.apache.pig.impl.plan.Operator
mKey
 
Constructor Summary
ConstantExpression(OperatorKey k)
           
ConstantExpression(OperatorKey k, int rp)
           
 
Method Summary
 ConstantExpression clone()
          Make a deep copy of this operator.
 List<ExpressionOperator> getChildExpressions()
          Get the child expressions of this expression
 Result getNextBigDecimal()
           
 Result getNextBigInteger()
           
 Result getNextBoolean()
           
 Result getNextDataBag()
           
 Result getNextDataByteArray()
           
 Result getNextDateTime()
           
 Result getNextDouble()
           
 Result getNextFloat()
           
 Result getNextInteger()
           
 Result getNextLong()
           
 Result getNextMap()
           
 Result getNextString()
           
 Result getNextTuple()
           
 Object getValue()
           
 Tuple illustratorMarkup(Object in, Object out, int eqClassIndex)
          input tuple mark up to be illustrate-able
 String name()
           
 void setValue(Object value)
           
 boolean supportsMultipleInputs()
          Indicates whether this operator supports multiple inputs.
 boolean supportsMultipleOutputs()
          Indicates whether this operator supports multiple outputs.
 void visit(PhyPlanVisitor v)
          Visit this node with the provided visitor.
 
Methods inherited from class org.apache.pig.backend.hadoop.executionengine.physicalLayer.expressionOperators.ExpressionOperator
accumChild, containUDF, setIllustrator, toString
 
Methods inherited from class org.apache.pig.backend.hadoop.executionengine.physicalLayer.PhysicalOperator
addOriginalLocation, addOriginalLocation, attachInput, cloneHelper, detachInput, getAlias, getAliasString, getIllustrator, getInputs, getLogger, getNext, getOriginalLocations, getPigLogger, getReporter, getRequestedParallelism, getResultType, isAccumStarted, isAccumulative, isBlocking, isInputAttached, processInput, reset, setAccumEnd, setAccumStart, setAccumulative, setInputs, setParentPlan, setPigLogger, setReporter, setRequestedParallelism, setResultType
 
Methods inherited from class org.apache.pig.impl.plan.Operator
compareTo, equals, getOperatorKey, getProjectionMap, hashCode, regenerateProjectionMap, rewire, unsetProjectionMap
 
Methods inherited from class java.lang.Object
finalize, getClass, notify, notifyAll, wait, wait, wait
 

Constructor Detail

ConstantExpression

public ConstantExpression(OperatorKey k)

ConstantExpression

public ConstantExpression(OperatorKey k,
                          int rp)
Method Detail

name

public String name()
Specified by:
name in class Operator<PhyPlanVisitor>

supportsMultipleInputs

public boolean supportsMultipleInputs()
Description copied from class: Operator
Indicates whether this operator supports multiple inputs.

Specified by:
supportsMultipleInputs in class Operator<PhyPlanVisitor>
Returns:
true if it does, otherwise false.

supportsMultipleOutputs

public boolean supportsMultipleOutputs()
Description copied from class: Operator
Indicates whether this operator supports multiple outputs.

Overrides:
supportsMultipleOutputs in class ExpressionOperator
Returns:
true if it does, otherwise false.

visit

public void visit(PhyPlanVisitor v)
           throws VisitorException
Description copied from class: Operator
Visit this node with the provided visitor. This should only be called by the visitor class itself, never directly.

Specified by:
visit in class ExpressionOperator
Parameters:
v - Visitor to visit with.
Throws:
VisitorException - if the visitor has a problem.

getValue

public Object getValue()

setValue

public void setValue(Object value)

getNextDataBag

public Result getNextDataBag()
                      throws ExecException
Overrides:
getNextDataBag in class ExpressionOperator
Throws:
ExecException

getNextDataByteArray

public Result getNextDataByteArray()
                            throws ExecException
Overrides:
getNextDataByteArray in class PhysicalOperator
Throws:
ExecException

getNextDouble

public Result getNextDouble()
                     throws ExecException
Overrides:
getNextDouble in class PhysicalOperator
Throws:
ExecException

getNextFloat

public Result getNextFloat()
                    throws ExecException
Overrides:
getNextFloat in class PhysicalOperator
Throws:
ExecException

getNextInteger

public Result getNextInteger()
                      throws ExecException
Overrides:
getNextInteger in class PhysicalOperator
Throws:
ExecException

getNextLong

public Result getNextLong()
                   throws ExecException
Overrides:
getNextLong in class PhysicalOperator
Throws:
ExecException

getNextDateTime

public Result getNextDateTime()
                       throws ExecException
Overrides:
getNextDateTime in class PhysicalOperator
Throws:
ExecException

getNextString

public Result getNextString()
                     throws ExecException
Overrides:
getNextString in class PhysicalOperator
Throws:
ExecException

getNextTuple

public Result getNextTuple()
                    throws ExecException
Overrides:
getNextTuple in class PhysicalOperator
Throws:
ExecException

getNextBoolean

public Result getNextBoolean()
                      throws ExecException
Overrides:
getNextBoolean in class PhysicalOperator
Throws:
ExecException

getNextMap

public Result getNextMap()
                  throws ExecException
Overrides:
getNextMap in class PhysicalOperator
Throws:
ExecException

getNextBigInteger

public Result getNextBigInteger()
                         throws ExecException
Overrides:
getNextBigInteger in class PhysicalOperator
Throws:
ExecException

getNextBigDecimal

public Result getNextBigDecimal()
                         throws ExecException
Overrides:
getNextBigDecimal in class PhysicalOperator
Throws:
ExecException

clone

public ConstantExpression clone()
                         throws CloneNotSupportedException
Description copied from class: ExpressionOperator
Make a deep copy of this operator. This is declared here to make it possible to call clone on ExpressionOperators.

Overrides:
clone in class ExpressionOperator
Throws:
CloneNotSupportedException
See Also:
Do not use the clone method directly. Operators are cloned when logical plans are cloned using {@link LogicalPlanCloner}

getChildExpressions

public List<ExpressionOperator> getChildExpressions()
Get the child expressions of this expression

Specified by:
getChildExpressions in class ExpressionOperator

illustratorMarkup

public Tuple illustratorMarkup(Object in,
                               Object out,
                               int eqClassIndex)
Description copied from interface: Illustrable
input tuple mark up to be illustrate-able

Parameters:
in - input tuple
out - output tuple before wrapped in ExampleTuple
eqClassIndex - index into equivalence classes in illustrator
Returns:
tuple


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