Package org.drools.core.reteoo.builder

Class PatternBuilder

java.lang.Object

org.drools.core.reteoo.builder.PatternBuilder

All Implemented Interfaces:

ReteooComponentBuilder

public class PatternBuilder
extends Object
implements ReteooComponentBuilder

A builder for patterns

Constructor Summary

Constructors

Constructor	Description
PatternBuilder()

Method Summary

Modifier and Type	Method	Description
void	attachAlphaNodes(BuildContext context, BuildUtils utils, List<AlphaNodeFieldConstraint> alphaConstraints)
void	build(BuildContext context, BuildUtils utils, RuleConditionElement rce)	Builds and attach if needed the given RuleConditionalElement
protected void	linkAlphaConstraint(AlphaNodeFieldConstraint constraint, List<AlphaNodeFieldConstraint> alphaConstraints)
protected void	linkBetaConstraint(BetaConstraint constraint, List<BetaConstraint> betaConstraints)
boolean	requiresLeftActivation(BuildUtils utils, RuleConditionElement rce)	A boolean function that indicates if the builder requires a previous left (tuple) activation in order to corretly build the given component.

Methods inherited from class java.lang.Object

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

Constructor Details

PatternBuilder

public PatternBuilder()

Method Details

build

public void build(BuildContext context,
 BuildUtils utils,
 RuleConditionElement rce)

Description copied from interface: ReteooComponentBuilder

Builds and attach if needed the given RuleConditionalElement

Specified by:

build in interface ReteooComponentBuilder

Parameters:

context - current build context

linkBetaConstraint

protected void linkBetaConstraint(BetaConstraint constraint,
 List<BetaConstraint> betaConstraints)

linkAlphaConstraint

protected void linkAlphaConstraint(AlphaNodeFieldConstraint constraint,
 List<AlphaNodeFieldConstraint> alphaConstraints)

attachAlphaNodes

public void attachAlphaNodes(BuildContext context,
 BuildUtils utils,
 List<AlphaNodeFieldConstraint> alphaConstraints)
                      throws InvalidPatternException

Throws:

InvalidPatternException

requiresLeftActivation

public boolean requiresLeftActivation(BuildUtils utils,
 RuleConditionElement rce)

Description copied from interface: ReteooComponentBuilder

A boolean function that indicates if the builder requires a previous left (tuple) activation in order to corretly build the given component. In other words, if it returns true and no previous TupleSource is already created, an InitialFact pattern must be added with appropriate left input adapter for the network to be correctly built. For instance, NOT / EXISTS / ACCUMULATE are examples of builders that must return true for this method, while PATTERN must return false.

Specified by:

requiresLeftActivation in interface ReteooComponentBuilder

rce - the element to be built

Returns:

true if a tuple source is required, false otherwise.