kget/core/job.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; either
   8    version 2 of the License, or (at your option) any later version.
   9 */
  10
  11 #ifndef JOB_H
  12 #define JOB_H
  13
  14 /**
  15  *  @brief Job class
  16  *
  17  *  We want to abstract this common interface in order to simplify the
  18  *  Scheduler code. A Job can be either a Transfer or a search through the net.
  19  *  It is basically something you execute in background and that the scheduler
  20  *  can decide to start, stop or cancel. In this way we don't expose the complex
  21  *  API of a Transfer (or a Search), to the scheduler.
  22  *  By definition a job must always belong to a JobQueue (see jobqueue.h).
  23  **/
  24
  25 #include "kget_export.h"
  26
  27 class QDomNode;
  28
  29 class Scheduler;
  30 class JobQueue;
  31
  32 class KGET_EXPORT Job
  33 {
  34     public:
  35         /**
  36          * The status property describes the current job status
  37          */
  38         enum Status {
  39             Running, /// The job is being executed
  40             Delayed, /// The job is delayed. This means that the scheduler should
  41                      /// not start it until it exits from the delayed state
  42             Stopped, /// The job is stopped
  43             Aborted, /// The job is stopped, but this also indicates that it
  44                      /// stopped because an error occurred
  45             Finished /// The job exited from its Running state successfully
  46         };
  47
  48         /**
  49          * The policy property describes how the scheduler should manage this job.
  50          */
  51         enum Policy {
  52             Start, /// The scheduler should start this job even if its queue
  53                    /// isn't in a Running status
  54             Stop,  /// The scheduler shouldn't never start this job, even if
  55                    /// if its queue is in a Running status
  56             None   /// The scheduler should start this job depending on its
  57                    /// queue status
  58         };
  59
  60         Job(JobQueue * parent, Scheduler * scheduler);
  61         virtual ~Job();
  62
  63         //Job commands
  64         virtual void start()=0;
  65         virtual void stop()=0;
  66
  67         virtual void setDelay(int seconds)=0;
  68         virtual void delayTimerEvent()=0;
  69
  70         virtual void postDeleteEvent() {}
  71
  72         JobQueue * jobQueue() {return m_jobQueue;}
  73
  74         //Job properties
  75         void setStatus(Status jobStatus);
  76         void setPolicy(Policy jobPolicy);
  77
  78         Status status() const {return m_status;}
  79         Policy policy() const {return m_policy;}
  80
  81         virtual int elapsedTime() const =0;
  82         virtual int remainingTime() const =0;
  83
  84         //Job capabilities
  85         virtual bool isResumable() const =0;
  86
  87     protected:
  88         Scheduler * scheduler() const {return m_scheduler;}
  89
  90         void read(QDomNode * n);
  91         void write(QDomNode * n);
  92
  93         /**
  94          * This one posts a job event to the scheduler
  95          */
  96         void postJobEvent(Status); //do we need a JobEvent instead of JobStatus?
  97
  98         JobQueue *  m_jobQueue;
  99         Scheduler * m_scheduler;
 100
 101     private:
 102         Status m_status;
 103         Policy m_policy;
 104 };
 105
 106 #endif