/**
* Loop over all currently started tasks and cycle them. This should be done after the classloader
* has been changed (e.g. during module start/stop)
*/
public void rescheduleAllTasks() throws SchedulerException {
for (TaskDefinition task : getScheduledTasks()) {
try {
rescheduleTask(task);
} catch (SchedulerException e) {
log.error("Failed to restart task: " + task.getName(), e);
}
}
}
/**
* Delete the task with the given identifier.
*
* @param id the identifier of the task
*/
public void deleteTask(Integer id) {
TaskDefinition task = getTask(id);
if (task.getStarted()) {
throw new APIException(
"Started tasks should not be deleted. They should be stopped first, and then deleted.");
}
// delete the task
getSchedulerDAO().deleteTask(id);
}
/**
* Get all scheduled tasks.
*
* @return all scheduled tasks
*/
public Collection<TaskDefinition> getScheduledTasks() {
// The real list of scheduled tasks is kept up-to-date in the scheduledTasks map
// TODO change the index for the scheduledTasks map to be the TaskDefinition rather than the ID
List<TaskDefinition> list = new ArrayList<TaskDefinition>();
Set<Integer> taskIds = scheduledTasks.keySet();
for (Integer id : taskIds) {
TaskDefinition task = getTask(id);
log.debug("Adding scheduled task " + id + " to list (" + task.getRepeatInterval() + ")");
list.add(task);
}
return list;
}
/**
* Stops a running task.
*
* @param taskDefinition the task to be stopped
* @see org.openmrs.scheduler.SchedulerService#shutdownTask(TaskDefinition)
*/
public void shutdownTask(TaskDefinition taskDefinition) throws SchedulerException {
if (taskDefinition != null) {
// Remove the task from the scheduled tasks and shutdown the timer
TimerSchedulerTask schedulerTask = scheduledTasks.remove(taskDefinition.getId());
if (schedulerTask != null) {
schedulerTask
.shutdown(); // Stops the timer and tells the timer task to release its resources
}
// Update task that has been started
taskDefinition.setStarted(false);
saveTask(taskDefinition);
}
}
/** Shutdown all running tasks. */
public void shutdownAllTasks() {
// iterate over this (copied) list of tasks and stop them all
for (TaskDefinition task : getScheduledTasks()) {
try {
shutdownTask(task);
} catch (SchedulerException e) {
log.error("Failed to stop task " + task.getTaskClass() + " due to Scheduler exception", e);
} catch (APIException e) {
log.error("Failed to stop task " + task.getTaskClass() + " due to API exception", e);
}
}
}
/**
* Save a task in the database.
*
* @param task the <code>TaskDefinition</code> to save
*/
public void saveTaskDefinition(TaskDefinition task) {
if (task.getId() != null) {
getSchedulerDAO().updateTask(task);
} else {
getSchedulerDAO().createTask(task);
}
}
/**
* Saves and stops all active tasks
*
* @return OpenmrsMemento
*/
public OpenmrsMemento saveToMemento() {
Set<Integer> tasks = new HashSet<Integer>();
for (TaskDefinition task : getScheduledTasks()) {
tasks.add(task.getId());
try {
shutdownTask(task);
} catch (SchedulerException e) {
// just swallow exceptions
log.debug("Failed to stop task while saving memento " + task.getName(), e);
}
}
TimerSchedulerMemento memento = new TimerSchedulerMemento(tasks);
memento.saveErrorTasks();
return memento;
}
/** Start up hook for the scheduler and all of its scheduled tasks. */
public void onStartup() {
log.debug("Starting scheduler service ...");
// Get all of the tasks in the database
Collection<TaskDefinition> taskDefinitions = getSchedulerDAO().getTasks();
// Iterate through the tasks and start them if their startOnStartup flag is true
if (taskDefinitions != null) {
for (TaskDefinition taskDefinition : taskDefinitions) {
try {
// If the task is configured to start on startup, we schedule it to run
// Otherwise it needs to be started manually.
if (taskDefinition.getStartOnStartup()) {
scheduleTask(taskDefinition);
}
} catch (Exception e) {
log.error("Failed to schedule task for class " + taskDefinition.getTaskClass(), e);
}
}
}
}
@Override
public void scheduleIfNotRunning(TaskDefinition taskDef) {
Task task = taskDef.getTaskInstance();
if (task == null) {
try {
scheduleTask(taskDef);
} catch (SchedulerException e) {
log.error("Failed to schedule task, because:", e);
}
} else if (!task.isExecuting()) {
try {
rescheduleTask(taskDef);
} catch (SchedulerException e) {
log.error("Failed to re-schedule task, because:", e);
}
}
}
/**
* Tests whether the TimerScheduler schedules tasks even if the repeatInterval is zero.
*
* @see {@link TimerSchedulerServiceImpl#scheduleTask(TaskDefinition)}
*/
@Test
@Verifies(value = "should handle zero repeat interval", method = "scheduleTask(TaskDefinition)")
public void scheduleTask_shouldHandleZeroRepeatInterval() throws Exception {
// Represents the start time of the task (right now)
Calendar startTime = Calendar.getInstance();
// Define repeatInterval as zero
Long repeatInterval = new Long(0);
String taskName = "TestTask";
String className = "org.openmrs.scheduler.tasks.TestTask";
Boolean startOnStartup = false;
// Create the new task
TaskDefinition taskDefinition = new TaskDefinition();
taskDefinition.setName(taskName);
taskDefinition.setTaskClass(className);
taskDefinition.setStartTime(startTime.getTime());
taskDefinition.setRepeatInterval(repeatInterval);
taskDefinition.setStartOnStartup(startOnStartup);
Task clientTask = null;
TimerSchedulerServiceImpl t = new TimerSchedulerServiceImpl();
clientTask = t.scheduleTask(taskDefinition);
// without this commit there seems to be a table lock left on the SCHEDULER_TASK_CONFIG table,
// see TRUNK-4212
Context.flushSession();
getConnection().commit();
// Assert that the clientTask is not null, i.e. the sheduleTask was able to successfully
// schedule in case of zero repeatInterval.
assertNotNull(
"The clientTask variable is null, so either the TimerSchedulerServiceImpl.scheduleTask method hasn't finished or didn't get run",
clientTask);
}
/**
* Schedule the given task according to the given schedule.
*
* @param taskDefinition the task to be scheduled
* @should should handle zero repeat interval
*/
public Task scheduleTask(TaskDefinition taskDefinition) throws SchedulerException {
Task clientTask = null;
if (taskDefinition != null) {
// Cancel any existing timer tasks for the same task definition
// TODO Make sure this is the desired behavior
// TODO Do we ever want the same task definition to run more than once?
TimerSchedulerTask schedulerTask = scheduledTasks.get(taskDefinition.getId());
if (schedulerTask != null) {
// schedulerTask.cancel();
log.info("Shutting down the existing instance of this task to avoid conflicts!!");
schedulerTask.shutdown();
}
try {
// Create new task from task definition
clientTask = TaskFactory.getInstance().createInstance(taskDefinition);
// if we were unable to get a class, just quit
if (clientTask != null) {
schedulerTask = new TimerSchedulerTask(clientTask);
taskDefinition.setTaskInstance(clientTask);
// Once this method is called, the timer is set to start at the given start time.
// NOTE: We need to adjust the repeat interval as the JDK Timer expects time in
// milliseconds and
// we record by seconds.
long repeatInterval = 0;
if (taskDefinition.getRepeatInterval() != null)
repeatInterval =
taskDefinition.getRepeatInterval() * SchedulerConstants.SCHEDULER_MILLIS_PER_SECOND;
if (taskDefinition.getStartTime() != null) {
// Need to calculate the "next execution time" because the scheduled time is most likely
// in the past
// and the JDK timer will run the task X number of times from the start time until now
// to catch up.
Date nextTime = SchedulerUtil.getNextExecution(taskDefinition);
// Start task at fixed rate at given future date and repeat as directed
log.info("Starting task ... the task will execute for the first time at " + nextTime);
if (repeatInterval > 0) {
// Schedule the task to run at a fixed rate
getTimer(taskDefinition).scheduleAtFixedRate(schedulerTask, nextTime, repeatInterval);
} else {
// Schedule the task to be non-repeating
getTimer(taskDefinition).schedule(schedulerTask, nextTime);
}
} else if (repeatInterval > 0) {
// Start task on repeating schedule, delay for SCHEDULER_DEFAULT_DELAY seconds
log.info(
"Delaying start time by "
+ SchedulerConstants.SCHEDULER_DEFAULT_DELAY
+ " seconds");
getTimer(taskDefinition)
.scheduleAtFixedRate(
schedulerTask, SchedulerConstants.SCHEDULER_DEFAULT_DELAY, repeatInterval);
} else {
// schedule for single execution, starting now
log.info("Starting one-shot task");
getTimer(taskDefinition).schedule(schedulerTask, new Date());
}
// Update task that has been started
log.debug("Registering timer for task " + taskDefinition.getId());
// Add the new timer to the scheduler running task list
scheduledTasks.put(taskDefinition.getId(), schedulerTask);
// Update the timer status in the database
taskDefinition.setStarted(true);
saveTask(taskDefinition);
}
} catch (Exception e) {
log.error("Failed to schedule task " + taskDefinition.getName(), e);
throw new SchedulerException("Failed to schedule task", e);
}
}
return clientTask;
}
