package org.eclipse.core.runtime; | |
/* | |
* (c) Copyright IBM Corp. 2000, 2001. | |
* All Rights Reserved. | |
*/ | |
/** | |
* The <code>IProgressMonitor</code> interface is implemented | |
* by objects that monitor the progress of an activity; the methods | |
* in this interface are invoked by code that performs the activity. | |
* <p> | |
* All activity is broken down into a linear sequence of tasks against | |
* which progress is reported. When a task begins, a <code>beginTask(String, int) | |
* </code> notification is reported, followed by any number and mixture of | |
* progress reports (<code>worked()</code>) and subtask notifications | |
* (<code>subTask(String)</code>). When the task is eventually completed, a | |
* <code>done()</code> notification is reported. After the <code>done()</code> | |
* notification, the progress monitor cannot be reused; i.e., <code> | |
* beginTask(String, int)</code> cannot be called again after the call to | |
* <code>done()</code>. | |
* </p> | |
* <p> | |
* A request to cancel an operation can be signaled using the | |
* <code>setCanceled</code> method. Operations taking a progress | |
* monitor are expected to poll the monitor (using <code>isCanceled</code>) | |
* periodically and abort at their earliest convenience. Operation can however | |
* choose to ignore cancelation requests. | |
* </p> | |
* <p> | |
* Since notification is synchronous with the activity itself, the listener should | |
* provide a fast and robust implementation. If the handling of notifications would | |
* involve blocking operations, or operations which might throw uncaught exceptions, | |
* the notifications should be queued, and the actual processing deferred (or perhaps | |
* delegated to a separate thread). | |
* </p> | |
* <p> | |
* Clients may implement this interface. | |
* </p> | |
*/ | |
public interface IProgressMonitor { | |
/** Constant indicating an unknown amount of work. | |
*/ | |
public final static int UNKNOWN = -1; | |
/** | |
* Notifies that the main task is beginning. This must only be called once | |
* on a given progress monitor instance. | |
* | |
* @param name the name (or description) of the main task | |
* @param totalWork the total number of work units into which | |
* the main task is been subdivided. If the value is <code>UNKNOWN</code> | |
* the implemenation is free to indicate progress in a way which | |
* doesn't require the total number of work units in advance. | |
*/ | |
public void beginTask(String name, int totalWork); | |
/** | |
* Notifies that the work is done; that is, either the main task is completed | |
* or the user canceled it. This method may be called more than once | |
* (implementations should be prepared to handle this case). | |
*/ | |
public void done(); | |
/** | |
* Internal method to handle scaling correctly. This method | |
* must not be called by a client. Clients should | |
* always use the method </code>worked(int)</code>. | |
*/ | |
public void internalWorked(double work); | |
/** | |
* Returns whether cancelation of current operation has been requested. | |
* Long-running operations should poll to see if cancelation | |
* has been requested. | |
* | |
* @return <code>true</code> if cancellation has been requested, | |
* and <code>false</code> otherwise | |
* @see #setCanceled | |
*/ | |
public boolean isCanceled(); | |
/** | |
* Sets the cancel state to the given value. | |
* | |
* @param value <code>true</code> indicates that cancelation has | |
* been requested (but not necessarily acknowledged); | |
* <code>false</code> clears this flag | |
* | |
* @see #isCanceled | |
*/ | |
public void setCanceled(boolean value); | |
/** | |
* Sets the task name to the given value. This method is used to | |
* restore the task label after a nested operation was executed. | |
* Normally there is no need for clients to call this method. | |
* | |
* @param name the name (or description) of the main task | |
* @see #beginTask(java.lang.String, int) | |
*/ | |
public void setTaskName(String name); | |
/** | |
* Notifies that a subtask of the main task is beginning. | |
* Subtasks are optional; the main task might not have subtasks. | |
* | |
* @param name the name (or description) of the subtask | |
*/ | |
public void subTask(String name); | |
/** | |
* Notifies that a given number of work unit of the main task | |
* has been completed. Note that this amount represents an | |
* installment, as opposed to a cumulative amount of work done | |
* to date. | |
* | |
* @param work the number of work units just completed | |
*/ | |
public void worked(int work); | |
} |