org.drools.rule
Class PredicateConstraint

java.lang.Object
  org.drools.rule.MutableTypeConstraint
      org.drools.rule.PredicateConstraint

All Implemented Interfaces:

Externalizable, Serializable, Cloneable, AlphaNodeFieldConstraint, BetaNodeFieldConstraint, Constraint, Restriction, RuleComponent, Wireable

public class PredicateConstraint
extends MutableTypeConstraint
implements Restriction, Wireable, 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

static class

PredicateConstraint.PredicateContextEntry

Nested classes/interfaces inherited from interface org.drools.spi.Constraint

Constraint.ConstraintType

Constructor Summary

PredicateConstraint()

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

PredicateConstraint(PredicateExpression evaluator)

PredicateConstraint(PredicateExpression expression, Declaration[] previousDeclarations, Declaration[] localDeclarations, String[] requiredGlobals, String[] requiredOperators)

Method Summary

PredicateConstraint	clone() Clones the constraint
ContextEntry	createContextEntry()
boolean	equals(Object object)
Evaluator	getEvaluator()
String[]	getGlobals()
Declaration[]	getLocalDeclarations()
String[]	getOperators()
PredicateExpression	getPredicateExpression()
Declaration[]	getPreviousDeclarations()
Declaration[]	getRequiredDeclarations() Returns all the declarations required by the given constraint implementation.
int	hashCode()
boolean	isAllowed(InternalFactHandle handle, InternalWorkingMemory workingMemory, ContextEntry ctx)
boolean	isAllowed(InternalReadAccessor extractor, InternalFactHandle handle, InternalWorkingMemory workingMemory, ContextEntry context)
boolean	isAllowedCachedLeft(ContextEntry context, InternalFactHandle handle)
boolean	isAllowedCachedRight(LeftTuple tuple, ContextEntry context)
boolean	isTemporal() Returns true if this is a temporal restriction
void	readExternal(ObjectInput in)
void	replaceDeclaration(Declaration oldDecl, Declaration newDecl) A restriction may be required to replace an old declaration object by a new updated one
void	setPredicateExpression(PredicateExpression expression)
String	toString()
void	wire(Object object)
void	writeExternal(ObjectOutput out)

Methods inherited from class org.drools.rule.MutableTypeConstraint

getType, setType

Methods inherited from class java.lang.Object

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

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,
                           String[] requiredGlobals,
                           String[] requiredOperators)

Method Detail

readExternal

public void readExternal(ObjectInput in)
                  throws IOException,
                         ClassNotFoundException

Specified by:

readExternal in interface Externalizable

Overrides:

readExternal in class MutableTypeConstraint

Throws:

IOException

ClassNotFoundException

writeExternal

public void writeExternal(ObjectOutput out)
                   throws IOException

Specified by:

writeExternal in interface Externalizable

Overrides:

writeExternal in class MutableTypeConstraint

Throws:

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

Specified by:

getRequiredDeclarations in interface Restriction

Returns:

getPreviousDeclarations

public Declaration[] getPreviousDeclarations()

getLocalDeclarations

public Declaration[] getLocalDeclarations()

getGlobals

public String[] getGlobals()

getOperators

public String[] getOperators()

replaceDeclaration

public void replaceDeclaration(Declaration oldDecl,
                               Declaration newDecl)

Description copied from interface: Restriction

A restriction may be required to replace an old declaration object by a new updated one

Specified by:

replaceDeclaration in interface Constraint

Specified by:

replaceDeclaration in interface Restriction

wire

public void wire(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: Restriction

Returns true if this is a temporal restriction

Specified by:

isTemporal in interface Constraint

Specified by:

isTemporal in interface Restriction

Returns:

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object object)

Overrides:

equals in class Object

createContextEntry

public ContextEntry createContextEntry()

Specified by:

createContextEntry in interface AlphaNodeFieldConstraint

Specified by:

createContextEntry in interface BetaNodeFieldConstraint

Specified by:

createContextEntry in interface Restriction

isAllowed

public boolean isAllowed(InternalFactHandle handle,
                         InternalWorkingMemory workingMemory,
                         ContextEntry ctx)

Specified by:

isAllowed in interface AlphaNodeFieldConstraint

isAllowed

public boolean isAllowed(InternalReadAccessor extractor,
                         InternalFactHandle handle,
                         InternalWorkingMemory workingMemory,
                         ContextEntry context)

Specified by:

isAllowed in interface Restriction

isAllowedCachedLeft

public boolean isAllowedCachedLeft(ContextEntry context,
                                   InternalFactHandle handle)

Specified by:

isAllowedCachedLeft in interface BetaNodeFieldConstraint

Specified by:

isAllowedCachedLeft in interface Restriction

isAllowedCachedRight

public boolean isAllowedCachedRight(LeftTuple tuple,
                                    ContextEntry context)

Specified by:

isAllowedCachedRight in interface BetaNodeFieldConstraint

Specified by:

isAllowedCachedRight in interface Restriction

clone

public PredicateConstraint clone()

Description copied from interface: Constraint

Clones the constraint

Specified by:

clone in interface Constraint

Specified by:

clone in interface Restriction

Specified by:

clone in class MutableTypeConstraint

Returns:

getEvaluator

public Evaluator getEvaluator()

Specified by:

getEvaluator in interface Restriction