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
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
|
/*
* Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* - Neither the name of Oracle nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
* IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
* THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
* EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/*
* This source code is provided to illustrate the usage of a given feature
* or technique and has been deliberately simplified. Additional steps
* required for a production-quality application, such as security checks,
* input validation and proper error handling, might not be present in
* this sample code.
*/
import java.nio.file.*;
import static java.nio.file.StandardCopyOption.*;
import java.nio.file.attribute.*;
import static java.nio.file.FileVisitResult.*;
import java.io.IOException;
import java.util.*;
/**
* Sample code that copies files in a similar manner to the cp(1) program.
*/
public class Copy {
/**
* Returns {@code true} if okay to overwrite a file ("cp -i")
*/
static boolean okayToOverwrite(Path file) {
String answer = System.console().readLine("overwrite %s (yes/no)? ", file);
return (answer.equalsIgnoreCase("y") || answer.equalsIgnoreCase("yes"));
}
/**
* Copy source file to target location. If {@code prompt} is true then
* prompt user to overwrite target if it exists. The {@code preserve}
* parameter determines if file attributes should be copied/preserved.
*/
static void copyFile(Path source, Path target, boolean prompt, boolean preserve) {
CopyOption[] options = (preserve) ?
new CopyOption[] { COPY_ATTRIBUTES, REPLACE_EXISTING } :
new CopyOption[] { REPLACE_EXISTING };
if (!prompt || Files.notExists(target) || okayToOverwrite(target)) {
try {
Files.copy(source, target, options);
} catch (IOException x) {
System.err.format("Unable to copy: %s: %s%n", source, x);
}
}
}
/**
* A {@code FileVisitor} that copies a file-tree ("cp -r")
*/
static class TreeCopier implements FileVisitor<Path> {
private final Path source;
private final Path target;
private final boolean prompt;
private final boolean preserve;
TreeCopier(Path source, Path target, boolean prompt, boolean preserve) {
this.source = source;
this.target = target;
this.prompt = prompt;
this.preserve = preserve;
}
@Override
public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
// before visiting entries in a directory we copy the directory
// (okay if directory already exists).
CopyOption[] options = (preserve) ?
new CopyOption[] { COPY_ATTRIBUTES } : new CopyOption[0];
Path newdir = target.resolve(source.relativize(dir));
try {
Files.copy(dir, newdir, options);
} catch (FileAlreadyExistsException x) {
// ignore
} catch (IOException x) {
System.err.format("Unable to create: %s: %s%n", newdir, x);
return SKIP_SUBTREE;
}
return CONTINUE;
}
@Override
public FileVisitResult visitFile(Path file, BasicFileAttributes attrs) {
copyFile(file, target.resolve(source.relativize(file)),
prompt, preserve);
return CONTINUE;
}
@Override
public FileVisitResult postVisitDirectory(Path dir, IOException exc) {
// fix up modification time of directory when done
if (exc == null && preserve) {
Path newdir = target.resolve(source.relativize(dir));
try {
FileTime time = Files.getLastModifiedTime(dir);
Files.setLastModifiedTime(newdir, time);
} catch (IOException x) {
System.err.format("Unable to copy all attributes to: %s: %s%n", newdir, x);
}
}
return CONTINUE;
}
@Override
public FileVisitResult visitFileFailed(Path file, IOException exc) {
if (exc instanceof FileSystemLoopException) {
System.err.println("cycle detected: " + file);
} else {
System.err.format("Unable to copy: %s: %s%n", file, exc);
}
return CONTINUE;
}
}
static void usage() {
System.err.println("java Copy [-ip] source... target");
System.err.println("java Copy -r [-ip] source-dir... target");
System.exit(-1);
}
public static void main(String[] args) throws IOException {
boolean recursive = false;
boolean prompt = false;
boolean preserve = false;
// process options
int argi = 0;
while (argi < args.length) {
String arg = args[argi];
if (!arg.startsWith("-"))
break;
if (arg.length() < 2)
usage();
for (int i=1; i<arg.length(); i++) {
char c = arg.charAt(i);
switch (c) {
case 'r' : recursive = true; break;
case 'i' : prompt = true; break;
case 'p' : preserve = true; break;
default : usage();
}
}
argi++;
}
// remaining arguments are the source files(s) and the target location
int remaining = args.length - argi;
if (remaining < 2)
usage();
Path[] source = new Path[remaining-1];
int i=0;
while (remaining > 1) {
source[i++] = Paths.get(args[argi++]);
remaining--;
}
Path target = Paths.get(args[argi]);
// check if target is a directory
boolean isDir = Files.isDirectory(target);
// copy each source file/directory to target
for (i=0; i<source.length; i++) {
Path dest = (isDir) ? target.resolve(source[i].getFileName()) : target;
if (recursive) {
// follow links when copying files
EnumSet<FileVisitOption> opts = EnumSet.of(FileVisitOption.FOLLOW_LINKS);
TreeCopier tc = new TreeCopier(source[i], dest, prompt, preserve);
Files.walkFileTree(source[i], opts, Integer.MAX_VALUE, tc);
} else {
// not recursive so source must not be a directory
if (Files.isDirectory(source[i])) {
System.err.format("%s: is a directory%n", source[i]);
continue;
}
copyFile(source[i], dest, prompt, preserve);
}
}
}
}
|
