/* 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.activiti.engine.impl.bpmn.behavior;
import java.util.ArrayList;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import org.activiti.engine.ActivitiException;
import org.activiti.engine.impl.Condition;
import org.activiti.engine.impl.bpmn.parser.BpmnParse;
import org.activiti.engine.impl.persistence.entity.ExecutionEntity;
import org.activiti.engine.impl.pvm.PvmActivity;
import org.activiti.engine.impl.pvm.PvmTransition;
import org.activiti.engine.impl.pvm.delegate.ActivityExecution;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
/**
* Implementation of the Inclusive Gateway/OR gateway/inclusive data-based
* gateway as defined in the BPMN specification.
*
* @author Tijs Rademakers
* @author Tom Van Buskirk
* @author Joram Barrez
*/
public class InclusiveGatewayActivityBehavior extends GatewayActivityBehavior {
private static final long serialVersionUID = 1L;
private static Logger log = LoggerFactory.getLogger(InclusiveGatewayActivityBehavior.class.getName());
public void execute(ActivityExecution execution) throws Exception {
execution.inactivate();
lockConcurrentRoot(execution);
PvmActivity activity = execution.getActivity();
if (!activeConcurrentExecutionsExist(execution)) {
if (log.isDebugEnabled()) {
log.debug("inclusive gateway '{}' activates", activity.getId());
}
List<ActivityExecution> joinedExecutions = execution.findInactiveConcurrentExecutions(activity);
String defaultSequenceFlow = (String) execution.getActivity().getProperty("default");
List<PvmTransition> transitionsToTake = new ArrayList<PvmTransition>();
for (PvmTransition outgoingTransition : execution.getActivity().getOutgoingTransitions()) {
if (defaultSequenceFlow == null || !outgoingTransition.getId().equals(defaultSequenceFlow)) {
Condition condition = (Condition) outgoingTransition.getProperty(BpmnParse.PROPERTYNAME_CONDITION);
if (condition == null || condition.evaluate(execution)) {
transitionsToTake.add(outgoingTransition);
}
}
}
if (!transitionsToTake.isEmpty()) {
execution.takeAll(transitionsToTake, joinedExecutions);
} else {
if (defaultSequenceFlow != null) {
PvmTransition defaultTransition = execution.getActivity().findOutgoingTransition(defaultSequenceFlow);
if (defaultTransition != null) {
execution.take(defaultTransition);
} else {
throw new ActivitiException("Default sequence flow '"
+ defaultSequenceFlow + "' could not be not found");
}
} else {
// No sequence flow could be found, not even a default one
throw new ActivitiException(
"No outgoing sequence flow of the inclusive gateway '"
+ execution.getActivity().getId()
+ "' could be selected for continuing the process");
}
}
} else {
if (log.isDebugEnabled()) {
log.debug("Inclusive gateway '{}' does not activate", activity.getId());
}
}
}
List<? extends ActivityExecution> getLeaveExecutions(ActivityExecution parent) {
List<ActivityExecution> executionlist = new ArrayList<ActivityExecution>();
List<? extends ActivityExecution> subExecutions = parent.getExecutions();
if (subExecutions.isEmpty()) {
executionlist.add(parent);
} else {
for (ActivityExecution concurrentExecution : subExecutions) {
executionlist.addAll(getLeaveExecutions(concurrentExecution));
}
}
return executionlist;
}
public boolean activeConcurrentExecutionsExist(ActivityExecution execution) {
PvmActivity activity = execution.getActivity();
if (execution.isConcurrent()) {
for (ActivityExecution concurrentExecution : getLeaveExecutions(execution.getParent())) {
if (concurrentExecution.isActive() && concurrentExecution.getId().equals(execution.getId()) == false) {
// TODO: when is transitionBeingTaken cleared? Should we clear it?
boolean reachable = false;
PvmTransition pvmTransition = ((ExecutionEntity) concurrentExecution).getTransitionBeingTaken();
if (pvmTransition != null) {
reachable = isReachable(pvmTransition.getDestination(), activity, new HashSet<PvmActivity>());
} else {
reachable = isReachable(concurrentExecution.getActivity(), activity, new HashSet<PvmActivity>());
}
if (reachable) {
if (log.isDebugEnabled()) {
log.debug("an active concurrent execution found: '{}'", concurrentExecution.getActivity());
}
return true;
}
}
}
} else if (execution.isActive()) { // is this ever true?
if (log.isDebugEnabled()) {
log.debug("an active concurrent execution found: '{}'", execution.getActivity());
}
return true;
}
return false;
}
protected boolean isReachable(PvmActivity srcActivity,
PvmActivity targetActivity, Set<PvmActivity> visitedActivities) {
// if source has no outputs, it is the end of the process, and its parent process should be checked.
if (srcActivity.getOutgoingTransitions().isEmpty()) {
visitedActivities.add(srcActivity);
if (!(srcActivity.getParent() instanceof PvmActivity)) {
return false;
}
srcActivity = (PvmActivity) srcActivity.getParent();
}
if (srcActivity.equals(targetActivity)) {
return true;
}
// To avoid infinite looping, we must capture every node we visit
// and check before going further in the graph if we have already visitied
// the node.
visitedActivities.add(srcActivity);
List<PvmTransition> transitionList = srcActivity.getOutgoingTransitions();
if (transitionList != null && !transitionList.isEmpty()) {
for (PvmTransition pvmTransition : transitionList) {
PvmActivity destinationActivity = pvmTransition.getDestination();
if (destinationActivity != null && !visitedActivities.contains(destinationActivity)) {
boolean reachable = isReachable(destinationActivity, targetActivity, visitedActivities);
// If false, we should investigate other paths, and not yet return the
// result
if (reachable) {
return true;
}
}
}
}
return false;
}
}