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A library jar that provides APIs for Applications written for the Google Android Platform.
/*
* Copyright (c) 2009, 2013, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package java.nio.file;
import java.util.Set;
import java.util.EnumSet;
import java.security.SecureRandom;
import static java.security.AccessController.*;
import java.io.IOException;
import java.nio.file.attribute.FileAttribute;
import java.nio.file.attribute.PosixFilePermission;
import java.nio.file.attribute.PosixFilePermissions;
import static java.nio.file.attribute.PosixFilePermission.*;
import sun.security.action.GetPropertyAction;
/**
* Helper class to support creation of temporary files and directories with
* initial attributes.
*/
class TempFileHelper {
private TempFileHelper() { }
// temporary directory location
private static final Path tmpdir =
Paths.get(doPrivileged(new GetPropertyAction("java.io.tmpdir")));
private static final boolean isPosix =
FileSystems.getDefault().supportedFileAttributeViews().contains("posix");
// file name generation, same as java.io.File for now
private static final SecureRandom random = new SecureRandom();
private static Path generatePath(String prefix, String suffix, Path dir) {
long n = random.nextLong();
n = (n == Long.MIN_VALUE) ? 0 : Math.abs(n);
Path name = dir.getFileSystem().getPath(prefix + Long.toString(n) + suffix);
// the generated name should be a simple file name
if (name.getParent() != null)
throw new IllegalArgumentException("Invalid prefix or suffix");
return dir.resolve(name);
}
// default file and directory permissions (lazily initialized)
private static class PosixPermissions {
static final FileAttribute> filePermissions =
PosixFilePermissions.asFileAttribute(EnumSet.of(OWNER_READ, OWNER_WRITE));
static final FileAttribute> dirPermissions =
PosixFilePermissions.asFileAttribute(EnumSet
.of(OWNER_READ, OWNER_WRITE, OWNER_EXECUTE));
}
/**
* Creates a file or directory in in the given given directory (or in the
* temporary directory if dir is {@code null}).
*/
private static Path create(Path dir,
String prefix,
String suffix,
boolean createDirectory,
FileAttribute[] attrs)
throws IOException
{
if (prefix == null)
prefix = "";
if (suffix == null)
suffix = (createDirectory) ? "" : ".tmp";
if (dir == null)
dir = tmpdir;
// in POSIX environments use default file and directory permissions
// if initial permissions not given by caller.
if (isPosix && (dir.getFileSystem() == FileSystems.getDefault())) {
if (attrs.length == 0) {
// no attributes so use default permissions
attrs = new FileAttribute[1];
attrs[0] = (createDirectory) ? PosixPermissions.dirPermissions :
PosixPermissions.filePermissions;
} else {
// check if posix permissions given; if not use default
boolean hasPermissions = false;
for (int i=0; i[] copy = new FileAttribute[attrs.length+1];
System.arraycopy(attrs, 0, copy, 0, attrs.length);
attrs = copy;
attrs[attrs.length-1] = (createDirectory) ?
PosixPermissions.dirPermissions :
PosixPermissions.filePermissions;
}
}
}
// loop generating random names until file or directory can be created
SecurityManager sm = System.getSecurityManager();
for (;;) {
Path f;
try {
f = generatePath(prefix, suffix, dir);
} catch (InvalidPathException e) {
// don't reveal temporary directory location
if (sm != null)
throw new IllegalArgumentException("Invalid prefix or suffix");
throw e;
}
try {
if (createDirectory) {
return Files.createDirectory(f, attrs);
} else {
return Files.createFile(f, attrs);
}
} catch (SecurityException e) {
// don't reveal temporary directory location
if (dir == tmpdir && sm != null)
throw new SecurityException("Unable to create temporary file or directory");
throw e;
} catch (FileAlreadyExistsException e) {
// ignore
}
}
}
/**
* Creates a temporary file in the given directory, or in in the
* temporary directory if dir is {@code null}.
*/
static Path createTempFile(Path dir,
String prefix,
String suffix,
FileAttribute[] attrs)
throws IOException
{
return create(dir, prefix, suffix, false, attrs);
}
/**
* Creates a temporary directory in the given directory, or in in the
* temporary directory if dir is {@code null}.
*/
static Path createTempDirectory(Path dir,
String prefix,
FileAttribute[] attrs)
throws IOException
{
return create(dir, prefix, null, true, attrs);
}
}