Module org.apache.jena.core

Package org.apache.jena.reasoner.rulesys.impl

Class RETEClauseFilter

java.lang.Object

org.apache.jena.reasoner.rulesys.impl.RETEClauseFilter

All Implemented Interfaces:

RETENode, RETESourceNode

public class RETEClauseFilter
extends Object
implements RETESourceNode

Checks a triple against the grounded matches and intra-triple matches for a single rule clause. If the match passes it creates a binding environment token and passes it on the RETE network itself. The checks and bindings are implemented using a simple byte-coded interpreter.

Field Summary

Fields

Modifier and Type	Field	Description
static final byte	ADDRFunctorNode	Argument addressing code: triple object functor node, offset in low nibble, only usable after a successful TestFunctorName.
static final byte	ADDRObject	Argument addressing code: triple object as a whole
static final byte	ADDRPredicate	Argument addressing code: triple predicate
static final byte	ADDRSubject	Argument addressing code: triple subject
static final byte	BIND	Instruction code: Bind a node (arg1) to a place in the rules token (arg2).
static final byte	CREATEToken	Instruction code: Create a result environment of length arg1.
static final byte	END	Instruction code: Final entry - dispatch to the network.
static final byte	TESTFunctorName	Instruction code: Check literal value is a functor of name arg1
static final byte	TESTIntraMatch	Instruction code: Cross match two triple entries (arg1, arg2)
static final byte	TESTValue	Instruction code: Check triple entry (arg1) against literal value (arg2).

Constructor Summary

Constructors

Constructor	Description
RETEClauseFilter(byte[] instructions, Object[] args)	Constructor.

Method Summary

Modifier and Type	Method	Description
RETENode	clone(Map<RETENode,RETENode> netCopy, RETERuleContext context)	Clone this node in the network.
static RETEClauseFilter	compile(TriplePattern clause, int envLength, List<Node> varList)	Create a filter node from a rule clause.
void	fire(Triple triple, boolean isAdd)	Insert or remove a triple into the network.
void	setContinuation(RETESinkNode continuation)	Set the continuation node for this node.

Methods inherited from class java.lang.Object

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

Field Details

TESTValue

public static final byte TESTValue

Instruction code: Check triple entry (arg1) against literal value (arg2).

See Also:

• Constant Field Values

TESTFunctorName

public static final byte TESTFunctorName

Instruction code: Check literal value is a functor of name arg1

See Also:

• Constant Field Values

TESTIntraMatch

public static final byte TESTIntraMatch

Instruction code: Cross match two triple entries (arg1, arg2)

See Also:

• Constant Field Values

CREATEToken

public static final byte CREATEToken

Instruction code: Create a result environment of length arg1.

See Also:

• Constant Field Values

BIND

public static final byte BIND

Instruction code: Bind a node (arg1) to a place in the rules token (arg2).

See Also:

• Constant Field Values

END

public static final byte END

Instruction code: Final entry - dispatch to the network.

See Also:

• Constant Field Values

ADDRSubject

public static final byte ADDRSubject

Argument addressing code: triple subject

See Also:

• Constant Field Values

ADDRPredicate

public static final byte ADDRPredicate

Argument addressing code: triple predicate

See Also:

• Constant Field Values

ADDRObject

public static final byte ADDRObject

Argument addressing code: triple object as a whole

See Also:

• Constant Field Values

ADDRFunctorNode

public static final byte ADDRFunctorNode

Argument addressing code: triple object functor node, offset in low nibble, only usable after a successful TestFunctorName.

See Also:

• Constant Field Values

Constructor Details

RETEClauseFilter

public RETEClauseFilter(byte[] instructions,
 Object[] args)

Constructor.

Parameters:

instructions - the set of byte-coded instructions and argument pointers.

args - the object arguments referenced from the instructions array.

Method Details

compile

public static RETEClauseFilter compile(TriplePattern clause,
 int envLength,
 List<Node> varList)

Create a filter node from a rule clause. Clause complexity is limited to less than 50 args in a Functor.

Parameters:

clause - the rule clause

envLength - the size of binding environment that should be created on successful matches

varList - a list to which all clause variables will be appended

setContinuation

public void setContinuation(RETESinkNode continuation)

Set the continuation node for this node.

Specified by:

setContinuation in interface RETESourceNode

fire

public void fire(Triple triple,
 boolean isAdd)

Insert or remove a triple into the network.

Parameters:

triple - the triple to process.

isAdd - true if the triple is being added to the working set.

clone

public RETENode clone(Map<RETENode,RETENode> netCopy,
 RETERuleContext context)

Clone this node in the network.

Specified by:

clone in interface RETENode

Parameters:

netCopy - a map from RETENode to cloned instance

context - the new context to which the network is being ported