1 /*

     2 * Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).

     3 * All rights reserved.

     4 * This component and the accompanying materials are made available

     5 * under the terms of "Eclipse Public License v1.0""

     6 * which accompanies this distribution, and is available

     7 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

     8 *

     9 * Initial Contributors:

    10 * Nokia Corporation - initial contribution.

    11 *

    12 * Contributors:

    13 *

    14 * Description:  

    15 *

    16 */

    17 #ifndef CPTASKEXECUTOR_H

    18 #define CPTASKEXECUTOR_H

    19 

    20 #include <cpcategoryglobal.h>

    21 #include <QThread>

    22 #include <QList>

    23 #include <QMutex>

    24 

    25 class CpTask

    26 {

    27 public:

    28     explicit CpTask(bool autoDelete = true) 

    29     : mAutoDelete(autoDelete)

    30     {

    31     }

    32 

    33     virtual ~CpTask()

    34     {

    35     }

    36 

    37     bool autoDelete() const 

    38     {

    39         return mAutoDelete;

    40     }

    41 

    42     virtual void execute(volatile bool *stopped)

    43     {

    44         Q_UNUSED(stopped);

    45     }

    46 

    47     virtual void complete(volatile bool *stopped)

    48     {

    49         Q_UNUSED(stopped);

    50     }

    51 

    52 private:

    53     bool mAutoDelete;

    54 };

    55 

    56 class CP_CATEGORY_EXPORT CpTaskExecutor : public QThread

    57 {

    58     Q_OBJECT

    59 public:

    60     explicit CpTaskExecutor(QObject *parent = 0);

    61 

    62     virtual ~CpTaskExecutor();

    63     

    64     /*

    65     return the gloabl instance

    66     */

    67     static CpTaskExecutor *globalInstance();

    68     

    69     /*

    70     destroy the global instance 

    71     */

    72     static void destroyGlobalInstance();

    73 

    74     /*

    75     add the task to running queue

    76     @task the task

    77     @append ture -- append to tail false -- preappend to head

    78     */

    79 

    80     bool runTask(CpTask *task,bool append = false);

    81 

    82     /*

    83     stop the thread and remove all not running tasks

    84     */

    85     void stop();

    86 

    87     /*

    88     move a task to front of the queue

    89     */

    90     bool toFront(CpTask *task);

    91 

    92     /*

    93     move a task to front of the queue

    94     */

    95     template <typename Predicate> bool toFront(Predicate pred);

    96 

    97 protected:

    98     /*

    99     From QThread, run tasks

   100     */

   101     virtual void run();

   102 private:

   103     /*

   104     remove not running tasks

   105     */

   106     void removeTasks();

   107 private:

   108     QList<CpTask*> mTasks;

   109     QMutex mMutex;

   110     volatile bool mStopped;

   111 };

   112 

   113 

   114 template<typename Predicate>

   115 bool CpTaskExecutor::toFront(Predicate pred)

   116 {

   117     QMutexLocker locker(&mMutex);

   118     

   119     QList<CpTask*>::iterator workIterator = mTasks.begin();

   120     QList<CpTask*>::iterator endIterator(mTasks.end());

   121 

   122     for(;workIterator != endIterator;++workIterator)

   123     {

   124         if (pred(*workIterator)) {

   125             break;

   126         }

   127     }

   128 

   129     if (workIterator == endIterator) {

   130         return false;

   131     }

   132 

   133     CpTask *task = *workIterator;

   134     mTasks.erase(workIterator);

   135     mTasks.insert(0,task);

   136 

   137     return true;

   138 }

   139 

   140 #endif  //CPTASKECECUTOR_H

   141 

   142 //End of File