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1   /*
2    * Copyright (C) 2007, Robin Rosenberg <robin.rosenberg@dewire.com>
3    * Copyright (C) 2008, Shawn O. Pearce <spearce@spearce.org>
4    * and other copyright owners as documented in the project's IP log.
5    *
6    * This program and the accompanying materials are made available
7    * under the terms of the Eclipse Distribution License v1.0 which
8    * accompanies this distribution, is reproduced below, and is
9    * available at http://www.eclipse.org/org/documents/edl-v10.php
10   *
11   * All rights reserved.
12   *
13   * Redistribution and use in source and binary forms, with or
14   * without modification, are permitted provided that the following
15   * conditions are met:
16   *
17   * - Redistributions of source code must retain the above copyright
18   *   notice, this list of conditions and the following disclaimer.
19   *
20   * - Redistributions in binary form must reproduce the above
21   *   copyright notice, this list of conditions and the following
22   *   disclaimer in the documentation and/or other materials provided
23   *   with the distribution.
24   *
25   * - Neither the name of the Eclipse Foundation, Inc. nor the
26   *   names of its contributors may be used to endorse or promote
27   *   products derived from this software without specific prior
28   *   written permission.
29   *
30   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
31   * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
32   * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
33   * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
35   * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
36   * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
37   * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
38   * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
39   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
40   * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
41   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
42   * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
43   */
44  
45  package org.eclipse.jgit.lib;
46  
47  /** A progress reporting interface. */
48  public interface ProgressMonitor {
49  	/** Constant indicating the total work units cannot be predicted. */
50  	public static final int UNKNOWN = 0;
51  
52  	/**
53  	 * Advise the monitor of the total number of subtasks.
54  	 * <p>
55  	 * This should be invoked at most once per progress monitor interface.
56  	 *
57  	 * @param totalTasks
58  	 *            the total number of tasks the caller will need to complete
59  	 *            their processing.
60  	 */
61  	void start(int totalTasks);
62  
63  	/**
64  	 * Begin processing a single task.
65  	 *
66  	 * @param title
67  	 *            title to describe the task. Callers should publish these as
68  	 *            stable string constants that implementations could match
69  	 *            against for translation support.
70  	 * @param totalWork
71  	 *            total number of work units the application will perform;
72  	 *            {@link #UNKNOWN} if it cannot be predicted in advance.
73  	 */
74  	void beginTask(String title, int totalWork);
75  
76  	/**
77  	 * Denote that some work units have been completed.
78  	 * <p>
79  	 * This is an incremental update; if invoked once per work unit the correct
80  	 * value for our argument is <code>1</code>, to indicate a single unit of
81  	 * work has been finished by the caller.
82  	 *
83  	 * @param completed
84  	 *            the number of work units completed since the last call.
85  	 */
86  	void update(int completed);
87  
88  	/** Finish the current task, so the next can begin. */
89  	void endTask();
90  
91  	/**
92  	 * Check for user task cancellation.
93  	 *
94  	 * @return true if the user asked the process to stop working.
95  	 */
96  	boolean isCancelled();
97  }