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
|
// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package org.chromium.base;
import android.content.Context;
import android.net.Uri;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.List;
import java.util.Locale;
/**
* Helper methods for dealing with Files.
*/
public class FileUtils {
private static final String TAG = "FileUtils";
/**
* Delete the given File and (if it's a directory) everything within it.
*/
public static void recursivelyDeleteFile(File currentFile) {
ThreadUtils.assertOnBackgroundThread();
if (currentFile.isDirectory()) {
File[] files = currentFile.listFiles();
if (files != null) {
for (File file : files) {
recursivelyDeleteFile(file);
}
}
}
if (!currentFile.delete()) Log.e(TAG, "Failed to delete: " + currentFile);
}
/**
* Delete the given files or directories by calling {@link #recursivelyDeleteFile(File)}.
* @param files The files to delete.
*/
public static void batchDeleteFiles(List<File> files) {
ThreadUtils.assertOnBackgroundThread();
for (File file : files) {
if (file.exists()) recursivelyDeleteFile(file);
}
}
/**
* Extracts an asset from the app's APK to a file.
* @param context
* @param assetName Name of the asset to extract.
* @param dest File to extract the asset to.
* @return true on success.
*/
public static boolean extractAsset(Context context, String assetName, File dest) {
InputStream inputStream = null;
OutputStream outputStream = null;
try {
inputStream = context.getAssets().open(assetName);
outputStream = new BufferedOutputStream(new FileOutputStream(dest));
byte[] buffer = new byte[8192];
int c;
while ((c = inputStream.read(buffer)) != -1) {
outputStream.write(buffer, 0, c);
}
inputStream.close();
outputStream.close();
return true;
} catch (IOException e) {
if (inputStream != null) {
try {
inputStream.close();
} catch (IOException ex) {
}
}
if (outputStream != null) {
try {
outputStream.close();
} catch (IOException ex) {
}
}
}
return false;
}
/**
* Atomically copies the data from an input stream into an output file.
* @param is Input file stream to read data from.
* @param outFile Output file path.
* @param buffer Caller-provided buffer. Provided to avoid allocating the same
* buffer on each call when copying several files in sequence.
* @throws IOException in case of I/O error.
*/
public static void copyFileStreamAtomicWithBuffer(InputStream is, File outFile, byte[] buffer)
throws IOException {
File tmpOutputFile = new File(outFile.getPath() + ".tmp");
try (OutputStream os = new FileOutputStream(tmpOutputFile)) {
Log.i(TAG, "Writing to %s", outFile);
int count = 0;
while ((count = is.read(buffer, 0, buffer.length)) != -1) {
os.write(buffer, 0, count);
}
}
if (!tmpOutputFile.renameTo(outFile)) {
throw new IOException();
}
}
/**
* Returns a URI that points at the file.
* @param file File to get a URI for.
* @return URI that points at that file, either as a content:// URI or a file:// URI.
*/
public static Uri getUriForFile(File file) {
// TODO(crbug/709584): Uncomment this when http://crbug.com/709584 has been fixed.
// assert !ThreadUtils.runningOnUiThread();
Uri uri = null;
try {
// Try to obtain a content:// URI, which is preferred to a file:// URI so that
// receiving apps don't attempt to determine the file's mime type (which often fails).
uri = ContentUriUtils.getContentUriFromFile(file);
} catch (IllegalArgumentException e) {
Log.e(TAG, "Could not create content uri: " + e);
}
if (uri == null) uri = Uri.fromFile(file);
return uri;
}
/**
* Returns the file extension, or an empty string if none.
* @param file Name of the file, with or without the full path.
* @return empty string if no extension, extension otherwise.
*/
public static String getExtension(String file) {
int index = file.lastIndexOf('.');
if (index == -1) return "";
return file.substring(index + 1).toLowerCase(Locale.US);
}
}
|
