kget/core/jobqueue.h

   1 /* This file is part of the KDE project
   2
   3    Copyright (C) 2005 Dario Massarin <nekkar@libero.it>
   4
   5    This program is free software; you can redistribute it and/or
   6    modify it under the terms of the GNU General Public
   7    License as published by the Free Software Foundation; version 2
   8    of the License.
   9 */
  10
  11
  12 #ifndef _JOBQUEUE_H
  13 #define _JOBQUEUE_H
  14
  15 /**
  16  * @brief JobQueue class
  17  *
  18  * This class abstracts the concept of queue. A queue is, basically, a
  19  * group of jobs that should be executed by the scheduler (if the queue
  20  * is marked as active). The scheduler will execute a maximum of n jobs
  21  * belonging to this queue at a time, where n can be set calling the
  22  * setMaxSimultaneousJobs(int n)
  23  *
  24  */
  25
  26 #include <QList>
  27 #include "kget_export.h"
  28
  29 class Job;
  30 class Scheduler;
  31
  32 class KGET_EXPORT JobQueue
  33 {
  34     public:
  35         enum Status {Running, Stopped};
  36         typedef QList<Job *>::iterator iterator;
  37
  38         JobQueue(Scheduler * scheduler);
  39         virtual ~JobQueue();
  40
  41         /**
  42          * Sets the JobQueue status
  43          *
  44          * @param queueStatus the new JobQueue status
  45          */
  46         virtual void setStatus(Status queueStatus);
  47
  48         /**
  49          * @return the jobQueue status
  50          */
  51         Status status() const   {return m_status;}
  52
  53         /**
  54          * @return the begin of the job's list
  55          */
  56         iterator begin()    {return m_jobs.begin();}
  57
  58         /**
  59          * @return the end of the job's list
  60          */
  61         iterator end()      {return m_jobs.end();}
  62
  63         /**
  64          * @return the last job in the job's list
  65          */
  66         Job * last()        {return m_jobs.last();}
  67
  68         /**
  69          * @return the number of jobs in the queue
  70          */
  71         int size() const    {return m_jobs.size();}
  72
  73         /**
  74          * @param job The job for which we want to find the index
  75          *
  76          * @return the job index for the given job. If the given
  77          *         job can't be found, it returns -1
  78          */
  79         int indexOf(Job * job) const    {return m_jobs.indexOf(job);}
  80
  81         /**
  82          * @returns the Job in the queue at the given index i
  83          */
  84         Job * operator[] (int i) const;
  85
  86         /**
  87          * @return a list with the running Jobs
  88          */
  89         const QList<Job *> runningJobs();
  90
  91         /**
  92          * Sets the maximum number of jobs belonging to this queue that
  93          * should executed simultaneously by the scheduler
  94          *
  95          * @param n The maximum number of jobs
  96          */
  97         void setMaxSimultaneousJobs(int n);
  98
  99         /**
 100          * @return the maximum number of jobs the scheduler should ever
 101          * execute simultaneously (in this queue).
 102          */
 103         int maxSimultaneousJobs() const;
 104
 105     protected:
 106         /**
 107          * appends a job to the current queue
 108          *
 109          * @param job The job to append to the current queue
 110          */
 111         void append(Job * job);
 112
 113         /**
 114          * prepends a job to the current queue
 115          *
 116          * @param job The job to prepend to the current queue
 117          */
 118         void prepend(Job * job);
 119
 120         /**
 121          * inserts a job to the current queue after the given job
 122          *
 123          * @param job The job to add in the current queue
 124          * @param after The job after which to add the job
 125          */
 126         void insert(Job * job, Job * after);
 127
 128         /**
 129          * removes a job from the current queue
 130          *
 131          * @param job The job to remove from the current queue
 132          */
 133         void remove(Job * job);
 134
 135         /**
 136          * Moves a job in the queue. Both the given jobs must belong to this queue
 137          *
 138          * @param job The job to move
 139          * @param position The job after which we have to move the given job
 140          */
 141         void move(Job * job, Job * after);
 142
 143         Scheduler * scheduler()     {return m_scheduler;}
 144
 145     private:
 146         QList<Job *> m_jobs;
 147
 148         int m_maxSimultaneousJobs;
 149
 150         Scheduler * m_scheduler;
 151         Status m_status;
 152 };
 153
 154 #endif