Package org.drools.core.rule

Class PredicateConstraint

java.lang.Object

org.drools.core.rule.MutableTypeConstraint

org.drools.core.rule.PredicateConstraint

All Implemented Interfaces:

java.io.Externalizable, java.io.Serializable, java.lang.Cloneable, Wireable, AlphaNodeFieldConstraint, BetaNodeFieldConstraint, Constraint, RuleComponent

public class PredicateConstraint
extends MutableTypeConstraint
implements Wireable, java.io.Externalizable

A predicate can be written as a top level constraint or be nested inside inside a field constraint (and as so, must implement the Restriction interface).

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	PredicateConstraint.PredicateContextEntry

Nested classes/interfaces inherited from interface org.drools.core.rule.constraint.Constraint

Constraint.ConstraintType

Nested classes/interfaces inherited from interface org.drools.core.rule.accessor.Wireable

Wireable.Immutable

Constructor Summary

Constructors

Constructor	Description
PredicateConstraint()
PredicateConstraint(PredicateExpression evaluator)
PredicateConstraint(PredicateExpression expression, Declaration[] previousDeclarations, Declaration[] localDeclarations)
PredicateConstraint(Declaration[] previousDeclarations, Declaration[] localDeclarations)

Method Summary

Modifier and Type	Method	Description
PredicateConstraint	clone()	Clones the constraint
ContextEntry	createContextEntry()
boolean	equals(java.lang.Object object)
Evaluator	getEvaluator()
PredicateExpression	getPredicateExpression()
Declaration[]	getRequiredDeclarations()	Returns all the declarations required by the given constraint implementation.
int	hashCode()
boolean	isAllowed(InternalFactHandle handle, ReteEvaluator reteEvaluator)
boolean	isAllowed(ReadAccessor extractor, InternalFactHandle handle, ReteEvaluator reteEvaluator, ContextEntry context)
boolean	isAllowedCachedLeft(ContextEntry context, InternalFactHandle handle)
boolean	isAllowedCachedRight(Tuple tuple, ContextEntry context)
boolean	isTemporal()	Returns true in case this constraint is a temporal constraint
void	readExternal(java.io.ObjectInput in)
void	replaceDeclaration(Declaration oldDecl, Declaration newDecl)	When a rule contains multiple logical branches, i.e., makes use of 'OR' CE, it is required to clone patterns and declarations for each logical branch.
void	setPredicateExpression(PredicateExpression expression)
java.lang.String	toString()
void	wire(java.lang.Object object)
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class org.drools.core.rule.MutableTypeConstraint

cloneIfInUse, getType, setInUse, setType

Methods inherited from class java.lang.Object

finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.drools.core.rule.constraint.Constraint

addPackageNames, equals, getListenedPropertyMask, getPackageNames, mergeEvaluationContext, registerEvaluationContext

Constructor Detail

PredicateConstraint

public PredicateConstraint()

PredicateConstraint

public PredicateConstraint(PredicateExpression evaluator)

PredicateConstraint

public PredicateConstraint(Declaration[] previousDeclarations,
                           Declaration[] localDeclarations)

PredicateConstraint

public PredicateConstraint(PredicateExpression expression,
                           Declaration[] previousDeclarations,
                           Declaration[] localDeclarations)

Method Detail

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Specified by:

readExternal in interface java.io.Externalizable

Overrides:

readExternal in class MutableTypeConstraint

Throws:

java.io.IOException

java.lang.ClassNotFoundException

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

Overrides:

writeExternal in class MutableTypeConstraint

Throws:

java.io.IOException

getRequiredDeclarations

public Declaration[] getRequiredDeclarations()

Description copied from interface: Constraint

Returns all the declarations required by the given constraint implementation.

Specified by:

getRequiredDeclarations in interface Constraint

Returns:

replaceDeclaration

public void replaceDeclaration(Declaration oldDecl,
                               Declaration newDecl)

Description copied from interface: Constraint

When a rule contains multiple logical branches, i.e., makes use of 'OR' CE, it is required to clone patterns and declarations for each logical branch. Since this is done at ReteOO build type, when constraints were already created, eventually some constraints need to update their references to the declarations.

Specified by:

replaceDeclaration in interface Constraint

wire

public void wire(java.lang.Object object)

Specified by:

wire in interface Wireable

setPredicateExpression

public void setPredicateExpression(PredicateExpression expression)

getPredicateExpression

public PredicateExpression getPredicateExpression()

isTemporal

public boolean isTemporal()

Description copied from interface: Constraint

Returns true in case this constraint is a temporal constraint

Specified by:

isTemporal in interface Constraint

Returns:

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object object)

Overrides:

equals in class java.lang.Object

createContextEntry

public ContextEntry createContextEntry()

Specified by:

createContextEntry in interface BetaNodeFieldConstraint

isAllowed

public boolean isAllowed(InternalFactHandle handle,
                         ReteEvaluator reteEvaluator)

Specified by:

isAllowed in interface AlphaNodeFieldConstraint

isAllowed

public boolean isAllowed(ReadAccessor extractor,
                         InternalFactHandle handle,
                         ReteEvaluator reteEvaluator,
                         ContextEntry context)

isAllowedCachedLeft

public boolean isAllowedCachedLeft(ContextEntry context,
                                   InternalFactHandle handle)

Specified by:

isAllowedCachedLeft in interface BetaNodeFieldConstraint

isAllowedCachedRight

public boolean isAllowedCachedRight(Tuple tuple,
                                    ContextEntry context)

Specified by:

isAllowedCachedRight in interface BetaNodeFieldConstraint

clone

public PredicateConstraint clone()

Description copied from interface: Constraint

Clones the constraint

Specified by:

clone in interface Constraint

Specified by:

clone in class MutableTypeConstraint

Returns:

getEvaluator

public Evaluator getEvaluator()