/*
* 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.IOException;
import java.io.ObjectInput;
import java.io.ObjectOutput;
import org.drools.base.DroolsQuery;
import org.drools.common.BaseNode;
import org.drools.common.InternalFactHandle;
import org.drools.common.InternalWorkingMemory;
import org.drools.common.PropagationContextImpl;
import org.drools.reteoo.builder.BuildContext;
import org.drools.rule.GroupElement;
import org.drools.rule.Query;
import org.drools.rule.Rule;
import org.drools.spi.PropagationContext;
/**
* Leaf Rete-OO node responsible for enacting <code>Action</code> s on a
* matched <code>Rule</code>.
*
* @see org.drools.rule.Rule
*/
public final class QueryTerminalNode extends BaseNode
implements
LeftTupleSinkNode,
TerminalNode {
// ------------------------------------------------------------
// Instance members
// ------------------------------------------------------------
private static final long serialVersionUID = 510l;
public static final short type = 8;
/** The rule to invoke upon match. */
private Rule rule;
private GroupElement subrule;
private LeftTupleSource tupleSource;
private LeftTupleSinkNode previousTupleSinkNode;
private LeftTupleSinkNode nextTupleSinkNode;
// ------------------------------------------------------------
// Constructors
// ------------------------------------------------------------
public QueryTerminalNode() {
}
/**
* Constructor
*
* @param id node ID
* @param source the tuple source for this node
* @param rule the rule this node belongs to
* @param subrule the subrule this node belongs to
* @param context the current build context
*/
public QueryTerminalNode(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.subrule = subrule;
this.tupleSource = source;
}
// ------------------------------------------------------------
// Instance methods
// ------------------------------------------------------------
public void readExternal(ObjectInput in) throws IOException,
ClassNotFoundException {
super.readExternal( in );
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.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;
}
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
// org.drools.impl.TupleSink
// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
/**
* Assert a new <code>Tuple</code>.
*
* @param tuple
* The <code>Tuple</code> being asserted.
* @param workingMemory
* The working memory seesion.
* @throws AssertionException
* If an error occurs while asserting.
*/
public void assertLeftTuple(final LeftTuple leftTuple,
final PropagationContext context,
final InternalWorkingMemory workingMemory) {
LeftTuple entry = leftTuple;
// find the DroolsQuery object
while ( entry.getParent() != null ) {
entry = entry.getParent();
}
DroolsQuery query = (DroolsQuery) entry.getLastHandle().getObject();
query.setQuery( (Query) this.rule );
// Add results to the adapter
query.getQueryResultCollector().rowAdded( this.rule,
leftTuple,
context,
workingMemory );
}
public void retractLeftTuple(final LeftTuple leftTuple,
final PropagationContext context,
final InternalWorkingMemory workingMemory) {
LeftTuple entry = leftTuple;
// find the DroolsQuery object
while ( entry.getParent() != null ) {
entry = entry.getParent();
}
DroolsQuery query = (DroolsQuery) entry.getLastHandle().getObject();
query.setQuery( (Query) this.rule );
// Add results to the adapter
query.getQueryResultCollector().rowRemoved( this.rule,
leftTuple,
context,
workingMemory );
}
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) {
LeftTuple entry = leftTuple;
// find the DroolsQuery object
while ( entry.getParent() != null ) {
entry = entry.getParent();
}
DroolsQuery query = (DroolsQuery) entry.getLastHandle().getObject();
query.setQuery( (Query) this.rule );
// Add results to the adapter
query.getQueryResultCollector().rowUpdated( this.rule,
leftTuple,
context,
workingMemory );
}
public String toString() {
return "[QueryTerminalNode(" + this.getId() + "): query=" + 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) {
this.tupleSource.remove( context,
builder,
this,
workingMemories );
}
public boolean isInUse() {
return false;
}
public void updateNewNode(final InternalWorkingMemory workingMemory,
final PropagationContext context) {
// There are no child nodes to update, do nothing.
}
public boolean isLeftTupleMemoryEnabled() {
return false;
}
public void setLeftTupleMemoryEnabled(boolean tupleMemoryEnabled) {
// do nothing, this can only ever be false
}
/**
* @return the subrule
*/
public GroupElement getSubrule() {
return this.subrule;
}
/**
* 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;
}
/**
* 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;
}
public short getType() {
return NodeTypeEnums.QueryTerminalNode;
}
}