xpcom/threads/nsISupportsPriority.idl

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  36
  37 #include "nsISupports.idl"
  38
  39 /**
  40  * This interface exposes the general notion of a scheduled object with a
  41  * integral priority value.  Following UNIX conventions, smaller (and possibly
  42  * negative) values have higher priority.
  43  *
  44  * This interface does not strictly define what happens when the priority of an
  45  * object is changed.  An implementation of this interface is free to define
  46  * the side-effects of changing the priority of an object.  In some cases,
  47  * changing the priority of an object may be disallowed (resulting in an
  48  * exception being thrown) or may simply be ignored.
  49  */
  50 [scriptable, uuid(aa578b44-abd5-4c19-8b14-36d4de6fdc36)]
  51 interface nsISupportsPriority : nsISupports
  52 {
  53   /**
  54    * Typical priority values.
  55    */
  56   const long PRIORITY_HIGHEST = -20;
  57   const long PRIORITY_HIGH    = -10;
  58   const long PRIORITY_NORMAL  =   0;
  59   const long PRIORITY_LOW     =  10;
  60   const long PRIORITY_LOWEST  =  20;
  61
  62   /**
  63    * This attribute may be modified to change the priority of this object.  The
  64    * implementation of this interface is free to truncate a given priority
  65    * value to whatever limits are appropriate.  Typically, this attribute is
  66    * initialized to PRIORITY_NORMAL, but implementations may choose to assign a
  67    * different initial value.
  68    */
  69   attribute long priority;
  70
  71   /**
  72    * This method adjusts the priority attribute by a given delta.  It helps
  73    * reduce the amount of coding required to increment or decrement the value
  74    * of the priority attribute.
  75    */
  76   void adjustPriority(in long delta);
  77 };