/**
* 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.workflow.instance.node;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import org.drools.common.InternalKnowledgeRuntime;
import org.drools.definition.process.Connection;
import org.drools.definition.process.Node;
import org.drools.process.core.context.exclusive.ExclusiveGroup;
import org.drools.process.instance.ContextInstanceContainer;
import org.drools.process.instance.InternalProcessRuntime;
import org.drools.process.instance.ProcessInstance;
import org.drools.process.instance.context.exclusive.ExclusiveGroupInstance;
import org.drools.process.instance.impl.ConstraintEvaluator;
import org.drools.runtime.process.NodeInstance;
import org.drools.workflow.core.node.Split;
import org.drools.workflow.instance.NodeInstanceContainer;
import org.drools.workflow.instance.impl.NodeInstanceImpl;
/**
* Runtime counterpart of a split node.
*
* @author <a href="mailto:kris_verlaenen@hotmail.com">Kris Verlaenen</a>
*/
public class SplitInstance extends NodeInstanceImpl {
private static final long serialVersionUID = 510l;
protected Split getSplit() {
return (Split) getNode();
}
public void internalTrigger(final NodeInstance from, String type) {
if (!org.drools.workflow.core.Node.CONNECTION_DEFAULT_TYPE.equals(type)) {
throw new IllegalArgumentException(
"A Split only accepts default incoming connections!");
}
final Split split = getSplit();
// TODO make different strategies for each type
switch ( split.getType() ) {
case Split.TYPE_AND :
triggerCompleted(org.drools.workflow.core.Node.CONNECTION_DEFAULT_TYPE, true);
break;
case Split.TYPE_XOR :
List<Connection> outgoing = split.getDefaultOutgoingConnections();
int priority = Integer.MAX_VALUE;
Connection selected = null;
for ( final Iterator<Connection> iterator = outgoing.iterator(); iterator.hasNext(); ) {
final Connection connection = (Connection) iterator.next();
ConstraintEvaluator constraint = (ConstraintEvaluator) split.getConstraint( connection );
if ( constraint != null && constraint.getPriority() < priority && !constraint.isDefault()) {
if ( constraint.evaluate( this,
connection,
constraint ) ) {
selected = connection;
priority = constraint.getPriority();
}
}
}
((NodeInstanceContainer) getNodeInstanceContainer()).removeNodeInstance(this);
if ( selected == null ) {
for ( final Iterator<Connection> iterator = outgoing.iterator(); iterator.hasNext(); ) {
final Connection connection = (Connection) iterator.next();
ConstraintEvaluator constraint = (ConstraintEvaluator) split.getConstraint( connection );
if ( constraint.isDefault() ) {
selected = connection;
break;
}
}
}
if ( selected == null ) {
throw new IllegalArgumentException( "XOR split could not find at least one valid outgoing connection for split " + getSplit().getName() );
}
triggerConnection(selected);
break;
case Split.TYPE_OR :
((NodeInstanceContainer) getNodeInstanceContainer()).removeNodeInstance(this);
outgoing = split.getDefaultOutgoingConnections();
boolean found = false;
List<Connection> outgoingCopy = new ArrayList<Connection>(outgoing);
while (!outgoingCopy.isEmpty()) {
priority = Integer.MAX_VALUE;
Connection selectedConnection = null;
ConstraintEvaluator selectedConstraint = null;
for ( final Iterator<Connection> iterator = outgoingCopy.iterator(); iterator.hasNext(); ) {
final Connection connection = (Connection) iterator.next();
ConstraintEvaluator constraint = (ConstraintEvaluator) split.getConstraint( connection );
if ( constraint != null
&& constraint.getPriority() < priority
&& !constraint.isDefault() ) {
priority = constraint.getPriority();
selectedConnection = connection;
selectedConstraint = constraint;
}
}
if (selectedConstraint == null) {
break;
}
if (selectedConstraint.evaluate( this,
selectedConnection,
selectedConstraint ) ) {
triggerConnection(selectedConnection);
found = true;
}
outgoingCopy.remove(selectedConnection);
}
if ( !found ) {
for ( final Iterator<Connection> iterator = outgoing.iterator(); iterator.hasNext(); ) {
final Connection connection = (Connection) iterator.next();
ConstraintEvaluator constraint = (ConstraintEvaluator) split.getConstraint( connection );
if ( constraint.isDefault() ) {
triggerConnection(connection);
found = true;
break;
}
}
}
if ( !found ) {
throw new IllegalArgumentException( "OR split could not find at least one valid outgoing connection for split " + getSplit().getName() );
}
break;
case Split.TYPE_XAND :
((org.drools.workflow.instance.NodeInstanceContainer) getNodeInstanceContainer()).removeNodeInstance(this);
Node node = getNode();
List<Connection> connections = null;
if (node != null) {
connections = node.getOutgoingConnections(type);
}
if (connections == null || connections.isEmpty()) {
((org.drools.workflow.instance.NodeInstanceContainer) getNodeInstanceContainer())
.nodeInstanceCompleted(this, type);
} else {
ExclusiveGroupInstance groupInstance = new ExclusiveGroupInstance();
org.drools.runtime.process.NodeInstanceContainer parent = getNodeInstanceContainer();
if (parent instanceof ContextInstanceContainer) {
((ContextInstanceContainer) parent).addContextInstance(ExclusiveGroup.EXCLUSIVE_GROUP, groupInstance);
} else {
throw new IllegalArgumentException(
"An Exclusive AND is only possible if the parent is a context instance container");
}
Map<NodeInstance, String> nodeInstances = new HashMap<NodeInstance, String>();
for (Connection connection: connections) {
nodeInstances.put(
((org.drools.workflow.instance.NodeInstanceContainer) getNodeInstanceContainer())
.getNodeInstance(connection.getTo()),
connection.getToType());
}
for (NodeInstance nodeInstance: nodeInstances.keySet()) {
groupInstance.addNodeInstance(nodeInstance);
}
for (Map.Entry<NodeInstance, String> entry: nodeInstances.entrySet()) {
// stop if this process instance has been aborted / completed
if (getProcessInstance().getState() != ProcessInstance.STATE_ACTIVE) {
return;
}
boolean hidden = false;
if (getNode().getMetaData().get("hidden") != null) {
hidden = true;
}
InternalKnowledgeRuntime kruntime = getProcessInstance().getKnowledgeRuntime();
if (!hidden) {
((InternalProcessRuntime) kruntime.getProcessRuntime())
.getProcessEventSupport().fireBeforeNodeLeft(this, kruntime);
}
((org.drools.workflow.instance.NodeInstance) entry.getKey())
.trigger(this, entry.getValue());
if (!hidden) {
((InternalProcessRuntime) kruntime.getProcessRuntime())
.getProcessEventSupport().fireAfterNodeLeft(this, kruntime);
}
}
}
break;
default :
throw new IllegalArgumentException( "Illegal split type " + split.getType() );
}
}
}