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/**

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

 *

 * <table class="striped" style="padding-left:2em; text-align:left">

 *     <caption style="display:none">Attribute views</caption>

 * <thead>

 * <tr><th scope="col">Attribute views</th>

 *     <th scope="col">Description</th></tr>

 * </thead>

 * <tbody>

 * <tr><th scope="row"><i>{@link java.nio.file.attribute.AttributeView}</i></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:1em"><i>{@link java.nio.file.attribute.FileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:2em">

 *     <i>{@link java.nio.file.attribute.BasicFileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:3em">

 *     <i>{@link java.nio.file.attribute.PosixFileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:3em">

 *     <i>{@link java.nio.file.attribute.DosFileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:2em">

 *     <i>{@link java.nio.file.attribute.FileOwnerAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:3em">

 *     <i>{@link java.nio.file.attribute.AclFileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:2em">

 *     <i>{@link java.nio.file.attribute.UserDefinedFileAttributeView}</i></span></th>

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

 * <tr><th scope="row">

 *     <span style="padding-left:1em"><i>{@link java.nio.file.attribute.FileStoreAttributeView}</i></span></th>

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

 * </tbody>

 * </table>

 *

 * <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 provide views to specific sets of file

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

 * java.nio.file.Files#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 Table (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> In addition to attribute views, this package also defines classes and

 * interfaces that are used when accessing attributes:

 *

 * <ul>

 *

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

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

 *   identity or group identity. </li>

 *

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

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

 *

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

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

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

 *

 * </ul>

 *

 *

 * <p> Unless otherwise noted, passing a {@code null} 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;