/*
 * Copyright (c) 2007, 2016, 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.attribute;

import java.io.IOException;

A file attribute view that supports reading or updating the owner of a file.
This file attribute view is intended for file system implementations that
support a file attribute that represents an identity that is the owner of
the file. Often the owner of a file is the identity of the entity that
created the file.
 The getOwner or setOwner methods may be used to read or update the owner of the file. 
 The getAttribute and setAttribute methods may also be used to read or update the owner. In that case, the owner attribute is identified by the name "owner", and the value of the attribute is a UserPrincipal. 
Since:
1.7/**
 * A file attribute view that supports reading or updating the owner of a file.
 * This file attribute view is intended for file system implementations that
 * support a file attribute that represents an identity that is the owner of
 * the file. Often the owner of a file is the identity of the entity that
 * created the file.
 *
 * <p> The {@link #getOwner getOwner} or {@link #setOwner setOwner} methods may
 * be used to read or update the owner of the file.
 *
 * <p> The {@link java.nio.file.Files#getAttribute getAttribute} and
 * {@link java.nio.file.Files#setAttribute setAttribute} methods may also be
 * used to read or update the owner. In that case, the owner attribute is
 * identified by the name {@code "owner"}, and the value of the attribute is
 * a {@link UserPrincipal}.
 *
 * @since 1.7
 */

public interface FileOwnerAttributeView
    extends FileAttributeView
{
    
Returns the name of the attribute view. Attribute views of this type have the name "owner". /**
     * Returns the name of the attribute view. Attribute views of this type
     * have the name {@code "owner"}.
     */
    @Override
    String name();

    
Read the file owner.
 It is implementation specific if the file owner can be a group. 
Throws:
IOException – 
         if an I/O error occurs
SecurityException –  In the case of the default provider, a security manager is installed, and it denies RuntimePermission("accessUserInformation") or its checkRead method denies read access to the file.
Returns:
 the file owner/**
     * Read the file owner.
     *
     * <p> It is implementation specific if the file owner can be a {@link
     * GroupPrincipal group}.
     *
     * @return  the file owner
     *
     * @throws  IOException
     *          if an I/O error occurs
     * @throws  SecurityException
     *          In the case of the default provider, a security manager is
     *          installed, and it denies {@link
     *          RuntimePermission}{@code ("accessUserInformation")} or its
     *          {@link SecurityManager#checkRead(String) checkRead} method
     *          denies read access to the file.
     */
    UserPrincipal getOwner() throws IOException;

    
Updates the file owner.
 It is implementation specific if the file owner can be a group. To ensure consistent and correct behavior across platforms it is recommended that this method should only be used to set the file owner to a user principal that is not a group. 
Params:
owner – 
         the new file owner
Throws:
IOException –  if an I/O error occurs, or the owner parameter is a group and this implementation does not support setting the owner to a group
SecurityException –  In the case of the default provider, a security manager is installed, and it denies RuntimePermission("accessUserInformation") or its checkWrite method denies write access to the file./**
     * Updates the file owner.
     *
     * <p> It is implementation specific if the file owner can be a {@link
     * GroupPrincipal group}. To ensure consistent and correct behavior
     * across platforms it is recommended that this method should only be used
     * to set the file owner to a user principal that is not a group.
     *
     * @param   owner
     *          the new file owner
     *
     * @throws  IOException
     *          if an I/O error occurs, or the {@code owner} parameter is a
     *          group and this implementation does not support setting the owner
     *          to a group
     * @throws  SecurityException
     *          In the case of the default provider, a security manager is
     *          installed, and it denies {@link
     *          RuntimePermission}{@code ("accessUserInformation")} or its
     *          {@link SecurityManager#checkWrite(String) checkWrite} method
     *          denies write access to the file.
     */
    void setOwner(UserPrincipal owner) throws IOException;
}