1 /*

     2  * Copyright (c) 2004, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 

    26 package sun.management;

    27 

    28 import java.io.File;

    29 import java.io.IOException;

    30 

    31 /*

    32  * Utility class to support file system operations

    33  *

    34  * @since 1.5

    35  */

    36 public abstract class FileSystem {

    37 

    38     private static final Object lock = new Object();

    39     private static FileSystem fs;

    40 

    41     protected FileSystem() { }

    42 

    43     /**

    44      * Opens the file system

    45      */

    46     public static FileSystem open() {

    47         synchronized (lock) {

    48             if (fs == null) {

    49                 fs = new FileSystemImpl();

    50             }

    51             return fs;

    52         }

    53     }

    54 

    55     /**

    56      * Tells whether or not the specified file is located on a

    57      * file system that supports file security or not.

    58      *

    59      * @throws  IOException     if an I/O error occurs.

    60      */

    61     public abstract boolean supportsFileSecurity(File f) throws IOException;

    62 

    63     /**

    64      * Tell whether or not the specified file is accessible

    65      * by anything other than the file owner.

    66      *

    67      * @throws  IOException     if an I/O error occurs.

    68      *

    69      * @throws  UnsupportedOperationException

    70      *          If file is located on a file system that doesn't support

    71      *          file security.

    72      */

    73     public abstract boolean isAccessUserOnly(File f) throws IOException;

    74 }