Java tutorial
/* * Copyright (c) 2007, 2009, 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; /** * Defines the standard open options. * * @since 1.7 */ public enum StandardOpenOption implements OpenOption { /** * Open for read access. */ READ, /** * Open for write access. */ WRITE, /** * If the file is opened for {@link #WRITE} access then bytes will be written * to the end of the file rather than the beginning. * * <p> If the file is opened for write access by other programs, then it * is file system specific if writing to the end of the file is atomic. */ APPEND, /** * If the file already exists and it is opened for {@link #WRITE} * access, then its length is truncated to 0. This option is ignored * if the file is opened only for {@link #READ} access. */ TRUNCATE_EXISTING, /** * Create a new file if it does not exist. * This option is ignored if the {@link #CREATE_NEW} option is also set. * The check for the existence of the file and the creation of the file * if it does not exist is atomic with respect to other file system * operations. */ CREATE, /** * Create a new file, failing if the file already exists. * The check for the existence of the file and the creation of the file * if it does not exist is atomic with respect to other file system * operations. */ CREATE_NEW, /** * Delete on close. When this option is present then the implementation * makes a <em>best effort</em> attempt to delete the file when closed * by the appropriate {@code close} method. If the {@code close} method is * not invoked then a <em>best effort</em> attempt is made to delete the * file when the Java virtual machine terminates (either normally, as * defined by the Java Language Specification, or where possible, abnormally). * This option is primarily intended for use with <em>work files</em> that * are used solely by a single instance of the Java virtual machine. This * option is not recommended for use when opening files that are open * concurrently by other entities. Many of the details as to when and how * the file is deleted are implementation specific and therefore not * specified. In particular, an implementation may be unable to guarantee * that it deletes the expected file when replaced by an attacker while the * file is open. Consequently, security sensitive applications should take * care when using this option. * * <p> For security reasons, this option may imply the {@link * LinkOption#NOFOLLOW_LINKS} option. In other words, if the option is present * when opening an existing file that is a symbolic link then it may fail * (by throwing {@link java.io.IOException}). */ DELETE_ON_CLOSE, /** * Sparse file. When used with the {@link #CREATE_NEW} option then this * option provides a <em>hint</em> that the new file will be sparse. The * option is ignored when the file system does not support the creation of * sparse files. */ SPARSE, /** * Requires that every update to the file's content or metadata be written * synchronously to the underlying storage device. * * @see <a href="package-summary.html#integrity">Synchronized I/O file integrity</a> */ SYNC, /** * Requires that every update to the file's content be written * synchronously to the underlying storage device. * * @see <a href="package-summary.html#integrity">Synchronized I/O file integrity</a> */ DSYNC; }