com.trolltech.qt.core
Class QFutureSynchronizer<T>

java.lang.Object
  extended by com.trolltech.qt.QSignalEmitter
      extended by com.trolltech.qt.QtJambiObject
          extended by com.trolltech.qt.core.QFutureSynchronizer<T>
All Implemented Interfaces:
QtJambiInterface

public class QFutureSynchronizer<T>
extends QtJambiObject

The QFutureSynchronizer class is a convenience class that simplifies QFuture synchronization. QFutureSynchronizer is a template class that simplifies synchronization of one or more QFuture objects. Futures are added using the addFuture() or setFuture() functions. The futures() function returns a list of futures. Use clearFutures() to remove all futures from the QFutureSynchronizer.

The waitForFinished() function waits for all futures to finish. The destructor of QFutureSynchronizer calls waitForFinished(), providing an easy way to ensure that all futures have finished before returning from a function:

The following code example is written in c++.

    void someFunction()
    {
        QFutureSynchronizer<void> synchronizer;

        ...

        synchronizer.addFuture(QtConcurrent::run(anotherFunction));
        synchronizer.addFuture(QtConcurrent::map(list, mapFunction));

        return; // QFutureSynchronizer waits for all futures to finish
    }
The behavior of waitForFinished() can be changed using the setCancelOnWait() function. Calling setCancelOnWait(true) will cause waitForFinished() to cancel all futures before waiting for them to finish. You can query the status of the cancel-on-wait feature using the cancelOnWait() function.

See also:
QFuture, QFutureWatcher, and Qt Concurrent.


Nested Class Summary
 
Nested classes/interfaces inherited from class com.trolltech.qt.QtJambiObject
QtJambiObject.QPrivateConstructor
 
Nested classes/interfaces inherited from class com.trolltech.qt.QSignalEmitter
QSignalEmitter.AbstractSignal, QSignalEmitter.Signal0, QSignalEmitter.Signal1<A>, QSignalEmitter.Signal2<A,B>, QSignalEmitter.Signal3<A,B,C>, QSignalEmitter.Signal4<A,B,C,D>, QSignalEmitter.Signal5<A,B,C,D,E>, QSignalEmitter.Signal6<A,B,C,D,E,F>, QSignalEmitter.Signal7<A,B,C,D,E,F,G>, QSignalEmitter.Signal8<A,B,C,D,E,F,G,H>, QSignalEmitter.Signal9<A,B,C,D,E,F,G,H,I>
 
Constructor Summary
  QFutureSynchronizer()
          Constructs a QFutureSynchronizer.
  QFutureSynchronizer(QFuture<T> future)
          Constructs a QFutureSynchronizer and begins watching future by calling addFuture().
protected QFutureSynchronizer(QtJambiObject.QPrivateConstructor p)
          This method is internal to Qt Jambi.
 
Method Summary
 void addFuture(QFuture<T> future)
          Adds future to the list of managed futures.
 boolean cancelOnWait()
          Returns true if the cancel-on-wait feature is enabled; otherwise returns false.
 void clearFutures()
          Removes all managed futures from this QFutureSynchronizer.
static QFutureSynchronizer fromNativePointer(QNativePointer nativePointer)
          This method returns the QFutureSynchronizer instance pointed to by nativePointer.
 java.util.List<QFuture<T>> futures()
          Returns a list of all managed futures.
 void setCancelOnWait(boolean enabled)
          Enables or disables the cancel-on-wait feature based on the enabled argument.
 void setFuture(QFuture<T> future)
          Sets future to be the only future managed by this QFutureSynchronizer.
 void waitForFinished()
          Waits for all futures to finish.
 
Methods inherited from class com.trolltech.qt.QtJambiObject
disableGarbageCollection, dispose, disposed, equals, finalize, nativeId, nativePointer, reassignNativeResources, reenableGarbageCollection, setJavaOwnership, tr, tr, tr
 
Methods inherited from class com.trolltech.qt.QSignalEmitter
__qt_signalInitialization, blockSignals, disconnect, disconnect, signalsBlocked, signalSender, thread
 
Methods inherited from class java.lang.Object
clone, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

QFutureSynchronizer

public QFutureSynchronizer()
Constructs a QFutureSynchronizer.


QFutureSynchronizer

public QFutureSynchronizer(QFuture<T> future)
Constructs a QFutureSynchronizer and begins watching future by calling addFuture().

See also:
addFuture().


QFutureSynchronizer

protected QFutureSynchronizer(QtJambiObject.QPrivateConstructor p)
This method is internal to Qt Jambi.

Method Detail

addFuture

public final void addFuture(QFuture<T> future)
Adds future to the list of managed futures.

See also:
futures().


cancelOnWait

public final boolean cancelOnWait()
Returns true if the cancel-on-wait feature is enabled; otherwise returns false. If cancel-on-wait is enabled, the waitForFinished() function will cancel all futures before waiting for them to finish.

See also:
setCancelOnWait(), and waitForFinished().


clearFutures

public final void clearFutures()
Removes all managed futures from this QFutureSynchronizer.

See also:
addFuture(), and setFuture().


setCancelOnWait

public final void setCancelOnWait(boolean enabled)
Enables or disables the cancel-on-wait feature based on the enabled argument. If enabled is true, the waitForFinished() function will cancel all futures before waiting for them to finish.

See also:
cancelOnWait(), and waitForFinished().


setFuture

public final void setFuture(QFuture<T> future)
Sets future to be the only future managed by this QFutureSynchronizer. This is a convenience function that calls waitForFinished(), then clearFutures(), and finally passes future to addFuture().

See also:
addFuture(), waitForFinished(), and clearFutures().


waitForFinished

public final void waitForFinished()
Waits for all futures to finish. If cancelOnWait() returns true, each future is canceled before waiting for them to finish.

See also:
cancelOnWait(), and setCancelOnWait().


fromNativePointer

public static QFutureSynchronizer fromNativePointer(QNativePointer nativePointer)
This method returns the QFutureSynchronizer instance pointed to by nativePointer.


futures

public final java.util.List<QFuture<T>> futures()
Returns a list of all managed futures.

See also:
addFuture(), and setFuture().