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
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
|
/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.os;
import android.util.Log;
import com.android.internal.os.RuntimeInit;
import java.lang.ref.WeakReference;
import java.util.ArrayList;
import java.util.HashMap;
public abstract class FileObserver {
/** File was accessed */
public static final int ACCESS = 0x00000001;
/** File was modified */
public static final int MODIFY = 0x00000002;
/** Metadata changed */
public static final int ATTRIB = 0x00000004;
/** Writable file was closed */
public static final int CLOSE_WRITE = 0x00000008;
/** Unwrittable file closed */
public static final int CLOSE_NOWRITE = 0x00000010;
/** File was opened */
public static final int OPEN = 0x00000020;
/** File was moved from X */
public static final int MOVED_FROM = 0x00000040;
/** File was moved to Y */
public static final int MOVED_TO = 0x00000080;
/** Subfile was created */
public static final int CREATE = 0x00000100;
/** Subfile was deleted */
public static final int DELETE = 0x00000200;
/** Self was deleted */
public static final int DELETE_SELF = 0x00000400;
/** Self was moved */
public static final int MOVE_SELF = 0x00000800;
public static final int ALL_EVENTS = ACCESS | MODIFY | ATTRIB | CLOSE_WRITE
| CLOSE_NOWRITE | OPEN | MOVED_FROM | MOVED_TO | DELETE | CREATE
| DELETE_SELF | MOVE_SELF;
private static final String LOG_TAG = "FileObserver";
private static class ObserverThread extends Thread {
private HashMap<Integer, WeakReference> m_observers = new HashMap<Integer, WeakReference>();
private int m_fd;
public ObserverThread() {
super("FileObserver");
m_fd = init();
}
public void run() {
observe(m_fd);
}
public int startWatching(String path, int mask, FileObserver observer) {
int wfd = startWatching(m_fd, path, mask);
Integer i = new Integer(wfd);
if (wfd >= 0) {
synchronized (m_observers) {
m_observers.put(i, new WeakReference(observer));
}
}
return i;
}
public void stopWatching(int descriptor) {
stopWatching(m_fd, descriptor);
}
public void onEvent(int wfd, int mask, String path) {
// look up our observer, fixing up the map if necessary...
FileObserver observer;
synchronized (m_observers) {
WeakReference weak = m_observers.get(wfd);
observer = (FileObserver) weak.get();
if (observer == null) {
m_observers.remove(wfd);
}
}
// ...then call out to the observer without the sync lock held
if (observer != null) {
try {
observer.onEvent(mask, path);
} catch (Throwable throwable) {
Log.e(LOG_TAG, "Unhandled throwable " + throwable.toString() +
" (returned by observer " + observer + ")", throwable);
RuntimeInit.crash("FileObserver", throwable);
}
}
}
private native int init();
private native void observe(int fd);
private native int startWatching(int fd, String path, int mask);
private native void stopWatching(int fd, int wfd);
}
private static ObserverThread s_observerThread;
static {
s_observerThread = new ObserverThread();
s_observerThread.start();
}
// instance
private String m_path;
private Integer m_descriptor;
private int m_mask;
public FileObserver(String path) {
this(path, ALL_EVENTS);
}
public FileObserver(String path, int mask) {
m_path = path;
m_mask = mask;
m_descriptor = -1;
}
protected void finalize() {
stopWatching();
}
public void startWatching() {
if (m_descriptor < 0) {
m_descriptor = s_observerThread.startWatching(m_path, m_mask, this);
}
}
public void stopWatching() {
if (m_descriptor >= 0) {
s_observerThread.stopWatching(m_descriptor);
m_descriptor = -1;
}
}
public abstract void onEvent(int event, String path);
}
|
