blob: 78ed7e2123aa5277d3defd9b27c82e1fd00d697c (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
|
/*
* Copyright (C) 2015, Google Inc. and others
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Distribution License v. 1.0 which is available at
* https://www.eclipse.org/org/documents/edl-v10.php.
*
* SPDX-License-Identifier: BSD-3-Clause
*/
package org.eclipse.jgit.transport;
import static java.nio.charset.StandardCharsets.UTF_8;
import java.io.IOException;
import java.io.OutputStream;
import java.util.concurrent.TimeUnit;
/**
* A simple spinner connected to an {@code OutputStream}.
* <p>
* This is class is not thread-safe. The update method may only be used from a
* single thread. Updates are sent only as frequently as {@link #update()} is
* invoked by the caller, and are capped at no more than 2 times per second by
* requiring at least 500 milliseconds between updates.
*
* @since 4.2
*/
public class ProgressSpinner {
private static final long MIN_REFRESH_MILLIS = 500;
private static final char[] STATES = new char[] { '-', '\\', '|', '/' };
private final OutputStream out;
private String msg;
private int state;
private boolean write;
private boolean shown;
private long nextUpdateMillis;
/**
* Initialize a new spinner.
*
* @param out
* where to send output to.
*/
public ProgressSpinner(OutputStream out) {
this.out = out;
this.write = true;
}
/**
* Begin a time consuming task.
*
* @param title
* description of the task, suitable for human viewing.
* @param delay
* delay to wait before displaying anything at all.
* @param delayUnits
* unit for {@code delay}.
*/
public void beginTask(String title, long delay, TimeUnit delayUnits) {
msg = title;
state = 0;
shown = false;
long now = System.currentTimeMillis();
if (delay > 0) {
nextUpdateMillis = now + delayUnits.toMillis(delay);
} else {
send(now);
}
}
/**
* Update the spinner if it is showing.
*/
public void update() {
long now = System.currentTimeMillis();
if (now >= nextUpdateMillis) {
send(now);
state = (state + 1) % STATES.length;
}
}
private void send(long now) {
StringBuilder buf = new StringBuilder(msg.length() + 16);
buf.append('\r').append(msg).append("... ("); //$NON-NLS-1$
buf.append(STATES[state]);
buf.append(") "); //$NON-NLS-1$
shown = true;
write(buf.toString());
nextUpdateMillis = now + MIN_REFRESH_MILLIS;
}
/**
* Denote the current task completed.
*
* @param result
* text to print after the task's title
* {@code "$title ... $result"}.
*/
public void endTask(String result) {
if (shown) {
write('\r' + msg + "... " + result + "\n"); //$NON-NLS-1$ //$NON-NLS-2$
}
}
private void write(String s) {
if (write) {
try {
out.write(s.getBytes(UTF_8));
out.flush();
} catch (IOException e) {
write = false;
}
}
}
}
|
