/* 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.delegate.event.impl;
import org.activiti.engine.delegate.event.ActivitiEntityEvent;
import org.activiti.engine.delegate.event.ActivitiEvent;
import org.activiti.engine.delegate.event.ActivitiEventDispatcher;
import org.activiti.engine.delegate.event.ActivitiEventListener;
import org.activiti.engine.delegate.event.ActivitiEventType;
import org.activiti.engine.impl.context.Context;
import org.activiti.engine.impl.interceptor.CommandContext;
import org.activiti.engine.impl.persistence.entity.ProcessDefinitionEntity;
import org.activiti.engine.repository.ProcessDefinition;
/**
* Class capable of dispatching events.
*
* @author Frederik Heremans
*/
public class ActivitiEventDispatcherImpl implements ActivitiEventDispatcher {
protected ActivitiEventSupport eventSupport;
protected boolean enabled = true;
public ActivitiEventDispatcherImpl() {
eventSupport = new ActivitiEventSupport();
}
public void setEnabled(boolean enabled) {
this.enabled = enabled;
}
public boolean isEnabled() {
return enabled;
}
@Override
public void addEventListener(ActivitiEventListener listenerToAdd) {
eventSupport.addEventListener(listenerToAdd);
}
@Override
public void addEventListener(ActivitiEventListener listenerToAdd, ActivitiEventType... types) {
eventSupport.addEventListener(listenerToAdd, types);
}
@Override
public void removeEventListener(ActivitiEventListener listenerToRemove) {
eventSupport.removeEventListener(listenerToRemove);
}
@Override
public void dispatchEvent(ActivitiEvent event) {
if (enabled) {
eventSupport.dispatchEvent(event);
}
// Check if a process context is active. If so, we also call the
// process-definition
// specific listeners (if any).
if (Context.isExecutionContextActive()) {
ProcessDefinitionEntity definition = Context.getExecutionContext().getProcessDefinition();
if (definition != null) {
definition.getEventSupport().dispatchEvent(event);
}
} else {
// Try getting hold of the Process definition, based on the process
// definition-key, if a context is active
CommandContext commandContext = Context.getCommandContext();
if (commandContext != null) {
ProcessDefinitionEntity processDefinition = extractProcessDefinitionEntityFromEvent(event);
if (processDefinition != null) {
processDefinition.getEventSupport().dispatchEvent(event);
}
}
}
}
/**
* In case no process-context is active, this method attempts to extract a
* process-definition based on the event. In case it's an event related to an
* entity, this can be deducted by inspecting the entity, without additional
* queries to the database.
*
* If not an entity-related event, the process-definition will be retrieved
* based on the processDefinitionId (if filled in). This requires an
* additional query to the database in case not already cached. However,
* queries will only occur when the definition is not yet in the cache, which
* is very unlikely to happen, unless evicted.
*
* @param event
* @return
*/
protected ProcessDefinitionEntity extractProcessDefinitionEntityFromEvent(ActivitiEvent event) {
ProcessDefinitionEntity result = null;
if (event.getProcessDefinitionId() != null) {
result = Context.getProcessEngineConfiguration().getDeploymentManager().getProcessDefinitionCache()
.get(event.getProcessDefinitionId());
if (result != null) {
result = Context.getProcessEngineConfiguration().getDeploymentManager().resolveProcessDefinition(result);
}
}
if(result == null && event instanceof ActivitiEntityEvent) {
Object entity = ((ActivitiEntityEvent) event).getEntity();
if(entity instanceof ProcessDefinition) {
result = (ProcessDefinitionEntity) entity;
}
}
return result;
}
}