| Interface | Description | 
|---|---|
| IProgressMonitor | The  IProgressMonitorinterface is implemented
 by objects that monitor the progress of an activity; the methods
 in this interface are invoked by code that performs the activity. | 
| Class | Description | 
|---|---|
| NullProgressMonitor | A default progress monitor implementation suitable for
 subclassing. | 
| SubMonitor | A progress monitor that uses a given amount of work ticks from a parent monitor. |