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/**

 * Interfaces and classes providing access to file and file system attributes.

 *

 * <blockquote><table cellspacing=1 cellpadding=0 summary="Attribute views">

 * <tr><th><p align="left">Attribute views</p></th><th><p align="left">Description</p></th></tr>

 * <tr><td valign=top><tt><i>{@link java.nio.file.attribute.AttributeView}</i></tt></td>

 *     <td>Can read or update non-opaque values associated with objects in a file system</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;<i>{@link java.nio.file.attribute.FileAttributeView}</i></tt></td>

 *     <td>Can read or update file attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.BasicFileAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update a basic set of file attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.PosixFileAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update POSIX defined file attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.DosFileAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update FAT file attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp<i>{@link java.nio.file.attribute.FileOwnerAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update the owner of a file</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.AclFileAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update Access Control Lists</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.UserDefinedFileAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read or update user-defined file attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;<i>{@link java.nio.file.attribute.FileStoreAttributeView}</i></tt></td>

 *     <td>Can read or update file system attributes</td></tr>

 * <tr><td valign=top><tt>&nbsp;&nbsp;&nbsp;&nbsp;<i>{@link java.nio.file.attribute.FileStoreSpaceAttributeView}&nbsp;&nbsp;</i></tt></td>

 *     <td>Can read file system <em>space usage</em> related attributes</td></tr>

 * </table></blockquote>

 *

 * <p> An attribute view provides a read-only or updatable view of the non-opaque

 * values, or <em>metadata</em>, associated with objects in a file system.

 * The {@link java.nio.file.attribute.FileAttributeView} interface is

 * extended by several other interfaces that that views to specific sets of file

 * attributes. {@code FileAttributeViews} are selected by invoking the {@link

 * java.nio.file.FileRef#getFileAttributeView} method with a

 * <em>type-token</em> to identify the required view. Views can also be identified

 * by name. The {@link java.nio.file.attribute.FileStoreAttributeView} interface

 * provides access to file store attributes. A {@code FileStoreAttributeView} of

 * a given type is obtained by invoking the {@link

 * java.nio.file.FileStore#getFileStoreAttributeView} method.

 *

 * <p> The {@link java.nio.file.attribute.BasicFileAttributeView}

 * class defines methods to read and update a <em>basic</em> set of file

 * attributes that are common to many file systems.

 *

 * <p> The {@link java.nio.file.attribute.PosixFileAttributeView}

 * interface extends {@code BasicFileAttributeView} by defining methods

 * to access the file attributes commonly used by file systems and operating systems

 * that implement the Portable Operating System Interface (POSIX) family of

 * standards.

 *

 * <p> The {@link java.nio.file.attribute.DosFileAttributeView}

 * class extends {@code BasicFileAttributeView} by defining methods to

 * access the legacy "DOS" file attributes supported on file systems such as File

 * Allocation Tabl (FAT), commonly used in consumer devices.

 *

 * <p> The {@link java.nio.file.attribute.AclFileAttributeView}

 * class defines methods to read and write the Access Control List (ACL)

 * file attribute. The ACL model used by this file attribute view is based

 * on the model defined by <a href="http://www.ietf.org/rfc/rfc3530.txt">

 * <i>RFC&nbsp;3530: Network File System (NFS) version 4 Protocol</i></a>.

 *

 * <p> The {@link java.nio.file.attribute.FileStoreSpaceAttributeView} class

 * defines methods to read file system space usage related attributes of a file system.

 *

 * <p> The {@link java.nio.file.attribute.Attributes} utility class defines

 * static methods to access file or file system attribute using the above

 * attribute views.

 *

 * <p> In addition to attribute views, this package also defines classes and

 * interfaces that are used when accessing attributes:

 *

 * <ul>

 *

 *   <p><li> The {@link java.nio.file.attribute.UserPrincipal} and

 *   {@link java.nio.file.attribute.GroupPrincipal} interfaces represent an

 *   identity or group identity. </li>

 *

 *   <p><li> The {@link java.nio.file.attribute.UserPrincipalLookupService}

 *   interface defines methods to lookup user or group principals. </li>

 *

 *   <p><li> The {@link java.nio.file.attribute.Attribute} interface

 *   represents the value of an attribute for cases where the attribute value is

 *   require to be set atomically when creating an object in the file system. </li>

 *

 * </ul>

 *

 *

 * <p> Unless otherwise noted, passing a <tt>null</tt> argument to a constructor

 * or method in any class or interface in this package will cause a {@link

 * java.lang.NullPointerException NullPointerException} to be thrown.

 *

 * @since 1.7

 */

package java.nio.file.attribute;