File Information
Library: Foundation
Package: Tasks
Header: Poco/TaskManager.h
Description
The TaskManager manages a collection of tasks and monitors their lifetime.
A TaskManager has a built-in NotificationCenter that is used to send out notifications on task progress and task states. See the TaskNotification class and its subclasses for the various events that result in a notification. To keep the number of notifications small, a TaskProgressNotification will only be sent out once in 100 milliseconds.
Member Summary
Member Functions: addObserver, cancelAll, count, joinAll, postNotification, removeObserver, start, taskCancelled, taskFailed, taskFinished, taskList, taskProgress, taskStarted
Types Aliases
TaskList
using TaskList = std::list < TaskPtr >;
TaskPtr
using TaskPtr = AutoPtr < Task >;
Constructors
TaskManager
TaskManager();
Creates the TaskManager, using the default ThreadPool.
TaskManager
TaskManager(
ThreadPool & pool
);
Creates the TaskManager, using the given ThreadPool.
Destructor
~TaskManager
~TaskManager();
Destroys the TaskManager.
Member Functions
addObserver
void addObserver(
const AbstractObserver & observer
);
Registers an observer with the NotificationCenter. Usage:
Observer<MyClass, MyNotification> obs(*this, &MyClass::handleNotification); notificationCenter.addObserver(obs);
cancelAll
void cancelAll();
Requests cancellation of all tasks.
count 
int count() const;
Returns the number of tasks in the internal task list.
joinAll
void joinAll();
Waits for the completion of all the threads in the TaskManager's thread pool.
Note: joinAll() will wait for ALL tasks in the TaskManager's ThreadPool to complete. If the ThreadPool has threads created by other facilities, these threads must also complete before joinAll() can return.
removeObserver
void removeObserver(
const AbstractObserver & observer
);
Unregisters an observer with the NotificationCenter.
start
void start(
Task * pTask
);
Starts the given task in a thread obtained from the thread pool.
The TaskManager takes ownership of the Task object and deletes it when it it finished.
taskList
TaskList taskList() const;
Returns a copy of the internal task list.
postNotification 
void postNotification(
const Notification::Ptr & pNf
);
Posts a notification to the task manager's notification center.
taskCancelled
void taskCancelled(
Task * pTask
);
taskFailed
void taskFailed(
Task * pTask,
const Exception & exc
);
taskFinished
void taskFinished(
Task * pTask
);
taskProgress
void taskProgress(
Task * pTask,
float progress
);
taskStarted
void taskStarted(
Task * pTask
);
Variables
MIN_PROGRESS_NOTIFICATION_INTERVAL 
static const int MIN_PROGRESS_NOTIFICATION_INTERVAL;