org.apache.pig.newplan.logical.rules

Class ConstantCalculator

java.lang.Object

org.apache.pig.newplan.optimizer.Rule

org.apache.pig.newplan.logical.rules.ConstantCalculator

Direct Known Subclasses:

FilterConstantCalculator, ForEachConstantCalculator

public abstract class ConstantCalculator
extends Rule

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ConstantCalculator.ConstantCalculatorTransformer

Field Summary

Fields inherited from class org.apache.pig.newplan.optimizer.Rule

currentPlan, log, name, pattern

Constructor Summary

Constructors

Constructor and Description
ConstantCalculator(java.lang.String n, PigContext pc)

Method Summary

Methods

Modifier and Type	Method and Description
Transformer	getNewTransformer() Get the transformer for this rule.

Methods inherited from class org.apache.pig.newplan.optimizer.Rule

buildPattern, getName, getPattern, isMandatory, isSkipListener, match, setSkipListener

Methods inherited from class java.lang.Object

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

Constructor Detail

ConstantCalculator

public ConstantCalculator(java.lang.String n,
                  PigContext pc)

Method Detail

getNewTransformer

public Transformer getNewTransformer()

Description copied from class: Rule

Get the transformer for this rule. Abstract because the rule may want to choose how to instantiate the transformer. This should never return a cached transformer, it should always return a fresh one with no state.

Specified by:

getNewTransformer in class Rule

Returns:

Transformer to use with this rule