1 /*
   2  * Copyright (c) 2007, 2009, 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 java.nio.file.attribute;
  27 
  28 import java.io.IOException;
  29 
  30 /**
  31  * A file attribute view that supports reading or updating the owner of a file.
  32  * This file attribute view is intended for file system implementations that
  33  * support a file attribute that represents an identity that is the owner of
  34  * the file. Often the owner of a file is the identity of the entity that
  35  * created the file.
  36  *
  37  * <p> The {@link #getOwner getOwner} or {@link #setOwner setOwner} methods may
  38  * be used to read or update the owner of the file.
  39  *
  40  * <p> The {@link java.nio.file.Files#getAttribute getAttribute} and
  41  * {@link java.nio.file.Files#setAttribute setAttribute} methods may also be
  42  * used to read or update the owner. In that case, the owner attribute is
  43  * identified by the name {@code "owner"}, and the value of the attribute is
  44  * a {@link UserPrincipal}.
  45  *
  46  * @since 1.7
  47  */
  48 
  49 public interface FileOwnerAttributeView
  50     extends FileAttributeView
  51 {
  52     /**
  53      * Returns the name of the attribute view. Attribute views of this type
  54      * have the name {@code "owner"}.
  55      */
  56     @Override
  57     String name();
  58 
  59     /**
  60      * Read the file owner.
  61      *
  62      * <p> It it implementation specific if the file owner can be a {@link
  63      * GroupPrincipal group}.
  64      *
  65      * @return  the file owner
  66      *
  67      * @throws  IOException
  68      *          if an I/O error occurs
  69      * @throws  SecurityException
  70      *          In the case of the default provider, a security manager is
  71      *          installed, and it denies {@link
  72      *          RuntimePermission}<tt>("accessUserInformation")</tt> or its
  73      *          {@link SecurityManager#checkRead(String) checkRead} method
  74      *          denies read access to the file.
  75      */
  76     UserPrincipal getOwner() throws IOException;
  77 
  78     /**
  79      * Updates the file owner.
  80      *
  81      * <p> It it implementation specific if the file owner can be a {@link
  82      * GroupPrincipal group}. To ensure consistent and correct behavior
  83      * across platforms it is recommended that this method should only be used
  84      * to set the file owner to a user principal that is not a group.
  85      *
  86      * @param   owner
  87      *          the new file owner
  88      *
  89      * @throws  IOException
  90      *          if an I/O error occurs, or the {@code owner} parameter is a
  91      *          group and this implementation does not support setting the owner
  92      *          to a group
  93      * @throws  SecurityException
  94      *          In the case of the default provider, a security manager is
  95      *          installed, and it denies {@link
  96      *          RuntimePermission}<tt>("accessUserInformation")</tt> or its
  97      *          {@link SecurityManager#checkWrite(String) checkWrite} method
  98      *          denies write access to the file.
  99      */
 100     void setOwner(UserPrincipal owner) throws IOException;
 101 }