org.drools.reteoo.builder
Class PatternBuilder

java.lang.Object
  org.drools.reteoo.builder.PatternBuilder

All Implemented Interfaces:

ReteooComponentBuilder

public class PatternBuilder
extends Object
implements ReteooComponentBuilder

A builder for patterns

Constructor Summary

PatternBuilder()

Method Summary

void	attachAlphaNodes(BuildContext context, BuildUtils utils, Pattern pattern, List<AlphaNodeFieldConstraint> alphaConstraints)
static ObjectTypeNode	attachObjectTypeNode(BuildContext context, ObjectType objectType)
void	build(BuildContext context, BuildUtils utils, RuleConditionElement rce) Builds and attach if needed the given RuleConditionalElement
protected void	buildAlphaNodeChain(BuildContext context, BuildUtils utils, Pattern pattern, List<AlphaNodeFieldConstraint> alphaConstraints)
protected void	linkAlphaConstraint(AlphaNodeFieldConstraint constraint, List<AlphaNodeFieldConstraint> alphaConstraints)
protected void	linkBetaConstraint(BetaNodeFieldConstraint constraint, List<BetaNodeFieldConstraint> 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 Detail

PatternBuilder

public PatternBuilder()

Method Detail

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(BetaNodeFieldConstraint constraint,
                                  List<BetaNodeFieldConstraint> betaConstraints)

linkAlphaConstraint

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

attachObjectTypeNode

public static ObjectTypeNode attachObjectTypeNode(BuildContext context,
                                                  ObjectType objectType)

attachAlphaNodes

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

Throws:

InvalidPatternException

buildAlphaNodeChain

protected void buildAlphaNodeChain(BuildContext context,
                                   BuildUtils utils,
                                   Pattern pattern,
                                   List<AlphaNodeFieldConstraint> alphaConstraints)

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.