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/*
* 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.ByteBuffer;
import java.nio.charset.Charset;
import java.nio.file.*;
import java.nio.file.attribute.*;
import java.io.IOException;
/**
* Example code to list/set/get/delete the user-defined attributes of a file.
*/
public class Xdd {
static void usage() {
System.out.println("Usage: java Xdd <file>");
System.out.println(" java Xdd -set <name>=<value> <file>");
System.out.println(" java Xdd -get <name> <file>");
System.out.println(" java Xdd -del <name> <file>");
System.exit(-1);
}
public static void main(String[] args) throws IOException {
// one or three parameters
if (args.length != 1 && args.length != 3)
usage();
Path file = (args.length == 1) ?
Paths.get(args[0]) : Paths.get(args[2]);
// check that user defined attributes are supported by the file store
FileStore store = Files.getFileStore(file);
if (!store.supportsFileAttributeView(UserDefinedFileAttributeView.class)) {
System.err.format("UserDefinedFileAttributeView not supported on %s\n", store);
System.exit(-1);
}
UserDefinedFileAttributeView view =
Files.getFileAttributeView(file, UserDefinedFileAttributeView.class);
// list user defined attributes
if (args.length == 1) {
System.out.println(" Size Name");
System.out.println("-------- --------------------------------------");
for (String name: view.list()) {
System.out.format("%8d %s\n", view.size(name), name);
}
return;
}
// Add/replace a file's user defined attribute
if (args[0].equals("-set")) {
// name=value
String[] s = args[1].split("=");
if (s.length != 2)
usage();
String name = s[0];
String value = s[1];
view.write(name, Charset.defaultCharset().encode(value));
return;
}
// Print out the value of a file's user defined attribute
if (args[0].equals("-get")) {
String name = args[1];
int size = view.size(name);
ByteBuffer buf = ByteBuffer.allocateDirect(size);
view.read(name, buf);
buf.flip();
System.out.println(Charset.defaultCharset().decode(buf).toString());
return;
}
// Delete a file's user defined attribute
if (args[0].equals("-del")) {
view.delete(args[1]);
return;
}
// option not recognized
usage();
}
}
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