/**
* Copyright 2005 JBoss Inc
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.drools.reteoo;
import java.io.Externalizable;
import java.io.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import org.drools.common.AgendaItem;
import org.drools.common.BaseNode;
import org.drools.common.EventFactHandle;
import org.drools.common.EventSupport;
import org.drools.common.InternalAgenda;
import org.drools.common.InternalFactHandle;
import org.drools.common.InternalRuleFlowGroup;
import org.drools.common.InternalWorkingMemory;
import org.drools.common.PropagationContextImpl;
import org.drools.common.ScheduledAgendaItem;
import org.drools.event.rule.ActivationCancelledCause;
import org.drools.reteoo.RuleRemovalContext.CleanupAdapter;
import org.drools.reteoo.builder.BuildContext;
import org.drools.rule.GroupElement;
import org.drools.rule.Rule;
import org.drools.spi.Activation;
import org.drools.spi.PropagationContext;
import org.drools.time.impl.Timer;
/**
* Leaf Rete-OO node responsible for enacting <code>Action</code> s on a
* matched <code>Rule</code>.
*
* @see org.drools.rule.Rule
*
* @author <a href="mailto:bob@eng.werken.com">bob mcwhirter </a>
*/
public class RuleTerminalNode extends BaseNode
implements
LeftTupleSinkNode,
TerminalNode,
Externalizable {
// ------------------------------------------------------------
// Instance members
// ------------------------------------------------------------
private int sequence = -1; // -1 means not set
/**
*
*/
private static final long serialVersionUID = 510l;
/** The rule to invoke upon match. */
private Rule rule;
/**
* the subrule reference is needed to resolve declarations
* because declarations may have different offsets in each subrule
*/
private GroupElement subrule;
private LeftTupleSource tupleSource;
private LeftTupleSinkNode previousTupleSinkNode;
private LeftTupleSinkNode nextTupleSinkNode;
protected boolean tupleMemoryEnabled;
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
public RuleTerminalNode() {
}
/**
* Construct.
*
* @param inputSource
* The parent tuple source.
* @param rule
* The rule.
*/
public RuleTerminalNode(final int id,
final LeftTupleSource source,
final Rule rule,
final GroupElement subrule,
final BuildContext context) {
super( id,
context.getPartitionId(),
context.getRuleBase().getConfiguration().isMultithreadEvaluation() );
this.rule = rule;
this.tupleSource = source;
this.subrule = subrule;
this.tupleMemoryEnabled = context.isTerminalNodeMemoryEnabled();
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
super.readExternal( in );
sequence = in.readInt();
rule = (Rule) in.readObject();
subrule = (GroupElement) in.readObject();
tupleSource = (LeftTupleSource) in.readObject();
previousTupleSinkNode = (LeftTupleSinkNode) in.readObject();
nextTupleSinkNode = (LeftTupleSinkNode) in.readObject();
}
public void writeExternal(ObjectOutput out) throws IOException {
super.writeExternal( out );
out.writeInt( sequence );
out.writeObject( rule );
out.writeObject( subrule );
out.writeObject( tupleSource );
out.writeObject( previousTupleSinkNode );
out.writeObject( nextTupleSinkNode );
}
/**
* Retrieve the <code>Action</code> associated with this node.
*
* @return The <code>Action</code> associated with this node.
*/
public Rule getRule() {
return this.rule;
}
public GroupElement getSubRule() {
return this.subrule;
}
public void setSequence(int seq) {
this.sequence = seq;
}
public int getSequence() {
return this.sequence;
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// org.drools.impl.TupleSink
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
public void assertLeftTuple(final LeftTuple tuple,
final PropagationContext context,
final InternalWorkingMemory workingMemory) {
//check if the rule is effective
if ( !this.rule.isEffective( tuple,
workingMemory ) ) {
return;
}
final InternalAgenda agenda = (InternalAgenda) workingMemory.getAgenda();
// if the current Rule is no-loop and the origin rule is the same then return
if ( this.rule.isNoLoop() && this.rule.equals( context.getRuleOrigin() ) ) {
agenda.increaseDormantActivations();
return;
}
final Timer timer = this.rule.getTimer();
if ( timer != null ) {
final ScheduledAgendaItem item = agenda.createScheduledAgendaItem( tuple,
context,
this.rule,
this.subrule );
agenda.scheduleItem( item,
workingMemory );
tuple.setObject( item );
item.setActivated( true );
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCreated( item,
workingMemory );
} else {
if ( this.rule.getCalendars() != null ) {
// for normal activations check for Calendar inclusion here, scheduled activations check on each trigger point
long timestamp = workingMemory.getSessionClock().getCurrentTime();
for ( String cal : this.rule.getCalendars() ) {
if ( !workingMemory.getCalendars().get( cal ).isTimeIncluded( timestamp ) ) {
return;
}
}
}
// -----------------
// Lazy instantiation and addition to the Agenda of AgendGroup
// implementations
// ----------------
final AgendaItem item = agenda.createAgendaItem( tuple,
rule.getSalience().getValue( tuple,
workingMemory ),
context,
this.rule,
this.subrule );
item.setSequenence( this.sequence );
tuple.setObject( item );
boolean added = agenda.addActivation( item );
if ( added ) {
item.setActivated( true );
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCreated( item,
workingMemory );
}
}
agenda.increaseActiveActivations();
}
public void retractLeftTuple(final LeftTuple leftTuple,
final PropagationContext context,
final InternalWorkingMemory workingMemory) {
final Activation activation = (Activation) leftTuple.getObject();
// activation can be null if the LeftTuple previous propagated into a no-loop
if ( activation == null ) {
return;
}
if ( activation.isActivated() ) {
// on fact expiration, we don't remove the activation, but let it fire
if ( context.getType() == PropagationContext.EXPIRATION && context.getFactHandleOrigin() != null ) {
EventFactHandle efh = (EventFactHandle) context.getFactHandleOrigin();
efh.increaseActivationsCount();
} else {
activation.remove();
if ( activation.getActivationGroupNode() != null ) {
activation.getActivationGroupNode().getActivationGroup().removeActivation( activation );
}
if ( activation.getActivationNode() != null ) {
final InternalRuleFlowGroup ruleFlowGroup = (InternalRuleFlowGroup) activation.getActivationNode().getParentContainer();
ruleFlowGroup.removeActivation( activation );
}
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCancelled( activation,
workingMemory,
ActivationCancelledCause.WME_MODIFY );
((InternalAgenda) workingMemory.getAgenda()).decreaseActiveActivations();
}
} else {
((InternalAgenda) workingMemory.getAgenda()).decreaseDormantActivations();
}
workingMemory.getTruthMaintenanceSystem().removeLogicalDependencies( activation,
context,
this.rule );
}
public void modifyLeftTuple(InternalFactHandle factHandle,
ModifyPreviousTuples modifyPreviousTuples,
PropagationContext context,
InternalWorkingMemory workingMemory) {
LeftTuple leftTuple = modifyPreviousTuples.removeLeftTuple( this );
if ( leftTuple != null ) {
leftTuple.reAdd(); //
// LeftTuple previously existed, so continue as modify
modifyLeftTuple( leftTuple,
context,
workingMemory );
} else {
// LeftTuple does not exist, so create and continue as assert
assertLeftTuple( new LeftTuple( factHandle,
this,
true ),
context,
workingMemory );
}
}
public void modifyLeftTuple(LeftTuple leftTuple,
PropagationContext context,
InternalWorkingMemory workingMemory) {
//check if the rule is effective
if ( !this.rule.isEffective( leftTuple,
workingMemory ) ) {
return;
}
AgendaItem item = (AgendaItem) leftTuple.getObject();
if ( item != null && item.isActivated() ) {
// already activated, do nothing
return;
}
final InternalAgenda agenda = (InternalAgenda) workingMemory.getAgenda();
// if the current Rule is no-loop and the origin rule is the same then return
if ( this.rule.isNoLoop() && this.rule.equals( context.getRuleOrigin() ) ) {
agenda.increaseDormantActivations();
return;
}
final Timer timer = this.rule.getTimer();
if ( timer != null ) {
if ( item == null ) {
item = agenda.createScheduledAgendaItem( leftTuple,
context,
this.rule,
this.subrule );
}
agenda.scheduleItem( (ScheduledAgendaItem) item,
workingMemory );
item.setActivated( true );
// workingMemory.removeLogicalDependencies( item,
// context,
// this.rule );
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCreated( item,
workingMemory );
} else {
if ( this.rule.getCalendars() != null ) {
// for normal activations check for Calendar inclusion here, scheduled activations check on each trigger point
long timestamp = workingMemory.getSessionClock().getCurrentTime();
for ( String cal : this.rule.getCalendars() ) {
if ( !workingMemory.getCalendars().get( cal ).isTimeIncluded( timestamp ) ) {
return;
}
}
}
if ( item == null ) {
// -----------------
// Lazy instantiation and addition to the Agenda of AgendGroup
// implementations
// ----------------
item = agenda.createAgendaItem( leftTuple,
rule.getSalience().getValue( leftTuple,
workingMemory ),
context,
this.rule,
this.subrule );
item.setSequenence( this.sequence );
} else {
item.setSalience( rule.getSalience().getValue( leftTuple,
workingMemory ) ); // need to re-evaluate salience, as used fields may have changed
item.setPropagationContext( context ); // update the Propagation Context
}
boolean added = agenda.addActivation( item );
item.setActivated( added );
if ( added ) {
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCreated( item,
workingMemory );
}
}
agenda.increaseActiveActivations();
}
public String toString() {
return "[RuleTerminalNode(" + this.getId() + "): rule=" + this.rule.getName() + "]";
}
public void ruleAttached() {
}
public void attach() {
this.tupleSource.addTupleSink( this );
}
public void attach(final InternalWorkingMemory[] workingMemories) {
attach();
for ( int i = 0, length = workingMemories.length; i < length; i++ ) {
final InternalWorkingMemory workingMemory = workingMemories[i];
final PropagationContext propagationContext = new PropagationContextImpl( workingMemory.getNextPropagationIdCounter(),
PropagationContext.RULE_ADDITION,
null,
null,
null );
this.tupleSource.updateSink( this,
propagationContext,
workingMemory );
}
}
public void networkUpdated() {
this.tupleSource.networkUpdated();
}
protected void doRemove(final RuleRemovalContext context,
final ReteooBuilder builder,
final BaseNode node,
final InternalWorkingMemory[] workingMemories) {
CleanupAdapter adapter = context.getCleanupAdapter();
context.setCleanupAdapter( new RTNCleanupAdapter( this ) );
this.tupleSource.remove( context,
builder,
this,
workingMemories );
for ( InternalWorkingMemory workingMemory : workingMemories ) {
workingMemory.executeQueuedActions();
}
context.setCleanupAdapter( adapter );
}
public boolean isInUse() {
return false;
}
public boolean isLeftTupleMemoryEnabled() {
return tupleMemoryEnabled;
}
public void setLeftTupleMemoryEnabled(boolean tupleMemoryEnabled) {
this.tupleMemoryEnabled = tupleMemoryEnabled;
}
/**
* Returns the next node
* @return
* The next TupleSinkNode
*/
public LeftTupleSinkNode getNextLeftTupleSinkNode() {
return this.nextTupleSinkNode;
}
/**
* Sets the next node
* @param next
* The next TupleSinkNode
*/
public void setNextLeftTupleSinkNode(final LeftTupleSinkNode next) {
this.nextTupleSinkNode = next;
}
/**
* Returns the previous node
* @return
* The previous TupleSinkNode
*/
public LeftTupleSinkNode getPreviousLeftTupleSinkNode() {
return this.previousTupleSinkNode;
}
/**
* Sets the previous node
* @param previous
* The previous TupleSinkNode
*/
public void setPreviousLeftTupleSinkNode(final LeftTupleSinkNode previous) {
this.previousTupleSinkNode = previous;
}
public int hashCode() {
return this.rule.hashCode();
}
public boolean equals(final Object object) {
if ( object == this ) {
return true;
}
if ( object == null || !(object instanceof RuleTerminalNode) ) {
return false;
}
final RuleTerminalNode other = (RuleTerminalNode) object;
return this.rule.equals( other.rule );
}
public short getType() {
return NodeTypeEnums.RuleTerminalNode;
}
public static class RTNCleanupAdapter
implements
CleanupAdapter {
private RuleTerminalNode node;
public RTNCleanupAdapter(RuleTerminalNode node) {
this.node = node;
}
public void cleanUp(final LeftTuple leftTuple,
final InternalWorkingMemory workingMemory) {
if ( leftTuple.getLeftTupleSink() != node ) {
return;
}
final Activation activation = (Activation) leftTuple.getObject();
if ( activation.isActivated() ) {
activation.remove();
((EventSupport) workingMemory).getAgendaEventSupport().fireActivationCancelled( activation,
workingMemory,
ActivationCancelledCause.CLEAR );
}
final PropagationContext propagationContext = new PropagationContextImpl( workingMemory.getNextPropagationIdCounter(),
PropagationContext.RULE_REMOVAL,
null,
null,
null );
workingMemory.getTruthMaintenanceSystem().removeLogicalDependencies( activation,
propagationContext,
node.getRule() );
leftTuple.unlinkFromLeftParent();
leftTuple.unlinkFromRightParent();
}
}
}