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/* * Copyright (c) 2007, 2017, 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 provides a view of a <em>basic set</em> of file * attributes common to many file systems. The basic set of file attributes * consist of <em>mandatory</em> and <em>optional</em> file attributes as * defined by the {@link BasicFileAttributes} interface. * <p> The file attributes are retrieved from the file system as a <em>bulk * operation</em> by invoking the {@link #readAttributes() readAttributes} method. * This class also defines the {@link #setTimes setTimes} method to update the * file's time attributes. * * <p> Where dynamic access to file attributes is required, the attributes * supported by this attribute view have the following names and types: * <blockquote> * <table class="striped"> * <caption style="display:none">Supported attributes</caption> * <thead> * <tr> * <th scope="col"> Name </th> * <th scope="col"> Type </th> * </tr> * </thead> * <tbody> * <tr> * <th scope="row"> "lastModifiedTime" </th> * <td> {@link FileTime} </td> * </tr> * <tr> * <th scope="row"> "lastAccessTime" </th> * <td> {@link FileTime} </td> * </tr> * <tr> * <th scope="row"> "creationTime" </th> * <td> {@link FileTime} </td> * </tr> * <tr> * <th scope="row"> "size" </th> * <td> {@link Long} </td> * </tr> * <tr> * <th scope="row"> "isRegularFile" </th> * <td> {@link Boolean} </td> * </tr> * <tr> * <th scope="row"> "isDirectory" </th> * <td> {@link Boolean} </td> * </tr> * <tr> * <th scope="row"> "isSymbolicLink" </th> * <td> {@link Boolean} </td> * </tr> * <tr> * <th scope="row"> "isOther" </th> * <td> {@link Boolean} </td> * </tr> * <tr> * <th scope="row"> "fileKey" </th> * <td> {@link Object} </td> * </tr> * </tbody> * </table> * </blockquote> * * <p> The {@link java.nio.file.Files#getAttribute getAttribute} method may be * used to read any of these attributes as if by invoking the {@link * #readAttributes() readAttributes()} method. * * <p> The {@link java.nio.file.Files#setAttribute setAttribute} method may be * used to update the file's last modified time, last access time or create time * attributes as if by invoking the {@link #setTimes setTimes} method. * * @since 1.7 */ public interface BasicFileAttributeView extends FileAttributeView { /** * Returns the name of the attribute view. Attribute views of this type * have the name {@code "basic"}. */ @Override String name(); /** * Reads the basic file attributes as a bulk operation. * * <p> It is implementation specific if all file attributes are read as an * atomic operation with respect to other file system operations. * * @return the file attributes * * @throws IOException * if an I/O error occurs * @throws SecurityException * In the case of the default provider, a security manager is * installed, its {@link SecurityManager#checkRead(String) checkRead} * method is invoked to check read access to the file */ BasicFileAttributes readAttributes() throws IOException; /** * Updates any or all of the file's last modified time, last access time, * and create time attributes. * * <p> This method updates the file's timestamp attributes. The values are * converted to the epoch and precision supported by the file system. * Converting from finer to coarser granularities result in precision loss. * The behavior of this method when attempting to set a timestamp that is * not supported or to a value that is outside the range supported by the * underlying file store is not defined. It may or not fail by throwing an * {@code IOException}. * * <p> If any of the {@code lastModifiedTime}, {@code lastAccessTime}, * or {@code createTime} parameters has the value {@code null} then the * corresponding timestamp is not changed. An implementation may require to * read the existing values of the file attributes when only some, but not * all, of the timestamp attributes are updated. Consequently, this method * may not be an atomic operation with respect to other file system * operations. Reading and re-writing existing values may also result in * precision loss. If all of the {@code lastModifiedTime}, {@code * lastAccessTime} and {@code createTime} parameters are {@code null} then * this method has no effect. * * <p> <b>Usage Example:</b> * Suppose we want to change a file's last access time. * <pre> * Path path = ... * FileTime time = ... * Files.getFileAttributeView(path, BasicFileAttributeView.class).setTimes(null, time, null); * </pre> * * @param lastModifiedTime * the new last modified time, or {@code null} to not change the * value * @param lastAccessTime * the last access time, or {@code null} to not change the value * @param createTime * the file's create time, or {@code null} to not change the value * * @throws IOException * if an I/O error occurs * @throws SecurityException * In the case of the default provider, a security manager is * installed, its {@link SecurityManager#checkWrite(String) checkWrite} * method is invoked to check write access to the file * * @see java.nio.file.Files#setLastModifiedTime */ void setTimes(FileTime lastModifiedTime, FileTime lastAccessTime, FileTime createTime) throws IOException; }