/*
 * Copyright (c) 1998, 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
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 */

package java.io;

import java.lang.annotation.Native;

/**
 * Package-private abstract class for the local filesystem abstraction.
 */

abstract class FileSystem {

 /* -- Normalization and construction -- */

 /**
 * Return the local filesystem's name-separator character.
 */
 public abstract char getSeparator();

 /**
 * Return the local filesystem's path-separator character.
 */
 public abstract char getPathSeparator();

 /**
 * Convert the given pathname string to normal form. If the string is
 * already in normal form then it is simply returned.
 */
 public abstract String normalize(String path);

 /**
 * Compute the length of this pathname string's prefix. The pathname
 * string must be in normal form.
 */
 public abstract int prefixLength(String path);

 /**
 * Resolve the child pathname string against the parent.
 * Both strings must be in normal form, and the result
 * will be in normal form.
 */
 public abstract String resolve(String parent, String child);

 /**
 * Return the parent pathname string to be used when the parent-directory
 * argument in one of the two-argument File constructors is the empty
 * pathname.
 */
 public abstract String getDefaultParent();

 /**
 * Post-process the given URI path string if necessary. This is used on
 * win32, e.g., to transform "/c:/foo" into "c:/foo". The path string
 * still has slash separators; code in the File class will translate them
 * after this method returns.
 */
 public abstract String fromURIPath(String path);


 /* -- Path operations -- */

 /**
 * Tell whether or not the given abstract pathname is absolute.
 */
 public abstract boolean isAbsolute(File f);

 /**
 * Resolve the given abstract pathname into absolute form. Invoked by the
 * getAbsolutePath and getCanonicalPath methods in the File class.
 */
 public abstract String resolve(File f);

 public abstract String canonicalize(String path) throws IOException;


 /* -- Attribute accessors -- */

 /* Constants for simple boolean attributes */
 @Native public static final int BA_EXISTS = 0x01;
 @Native public static final int BA_REGULAR = 0x02;
 @Native public static final int BA_DIRECTORY = 0x04;
 @Native public static final int BA_HIDDEN = 0x08;

 /**
 * Return the simple boolean attributes for the file or directory denoted
 * by the given abstract pathname, or zero if it does not exist or some
 * other I/O error occurs.
 */
 public abstract int getBooleanAttributes(File f);

 @Native public static final int ACCESS_READ = 0x04;
 @Native public static final int ACCESS_WRITE = 0x02;
 @Native public static final int ACCESS_EXECUTE = 0x01;

 /**
 * Check whether the file or directory denoted by the given abstract
 * pathname may be accessed by this process. The second argument specifies
 * which access, ACCESS_READ, ACCESS_WRITE or ACCESS_EXECUTE, to check.
 * Return false if access is denied or an I/O error occurs
 */
 public abstract boolean checkAccess(File f, int access);
 /**
 * Set on or off the access permission (to owner only or to all) to the file
 * or directory denoted by the given abstract pathname, based on the parameters
 * enable, access and oweronly.
 */
 public abstract boolean setPermission(File f, int access, boolean enable, boolean owneronly);

 /**
 * Return the time at which the file or directory denoted by the given
 * abstract pathname was last modified, or zero if it does not exist or
 * some other I/O error occurs.
 */
 public abstract long getLastModifiedTime(File f);

 /**
 * Return the length in bytes of the file denoted by the given abstract
 * pathname, or zero if it does not exist, is a directory, or some other
 * I/O error occurs.
 */
 public abstract long getLength(File f);


 /* -- File operations -- */

 /**
 * Create a new empty file with the given pathname. Return
 * <code>true</code> if the file was created and <code>false</code> if a
 * file or directory with the given pathname already exists. Throw an
 * IOException if an I/O error occurs.
 */
 public abstract boolean createFileExclusively(String pathname)
 throws IOException;

 /**
 * Delete the file or directory denoted by the given abstract pathname,
 * returning <code>true</code> if and only if the operation succeeds.
 */
 public abstract boolean delete(File f);

 /**
 * List the elements of the directory denoted by the given abstract
 * pathname. Return an array of strings naming the elements of the
 * directory if successful; otherwise, return <code>null</code>.
 */
 public abstract String[] list(File f);

 /**
 * Create a new directory denoted by the given abstract pathname,
 * returning <code>true</code> if and only if the operation succeeds.
 */
 public abstract boolean createDirectory(File f);

 /**
 * Rename the file or directory denoted by the first abstract pathname to
 * the second abstract pathname, returning <code>true</code> if and only if
 * the operation succeeds.
 */
 public abstract boolean rename(File f1, File f2);

 /**
 * Set the last-modified time of the file or directory denoted by the
 * given abstract pathname, returning <code>true</code> if and only if the
 * operation succeeds.
 */
 public abstract boolean setLastModifiedTime(File f, long time);

 /**
 * Mark the file or directory denoted by the given abstract pathname as
 * read-only, returning <code>true</code> if and only if the operation
 * succeeds.
 */
 public abstract boolean setReadOnly(File f);


 /* -- Filesystem interface -- */

 /**
 * List the available filesystem roots.
 */
 public abstract File[] listRoots();

 /* -- Disk usage -- */
 @Native public static final int SPACE_TOTAL = 0;
 @Native public static final int SPACE_FREE = 1;
 @Native public static final int SPACE_USABLE = 2;

 public abstract long getSpace(File f, int t);

 /* -- Basic infrastructure -- */

 /**
 * Retrieve the maximum length of a component of a file path.
 *
 * @return The maximum length of a file path component.
 */
 public abstract int getNameMax(String path);

 /**
 * Compare two abstract pathnames lexicographically.
 */
 public abstract int compare(File f1, File f2);

 /**
 * Compute the hash code of an abstract pathname.
 */
 public abstract int hashCode(File f);

 // Flags for enabling/disabling performance optimizations for file
 // name canonicalization
 static final boolean useCanonCaches;
 static final boolean useCanonPrefixCache;

 private static boolean getBooleanProperty(String prop, boolean defaultVal) {
 String value = System.getProperty(prop);
 return (value != null) ? Boolean.parseBoolean(value) : defaultVal;
 }

 static {
 useCanonCaches = getBooleanProperty("sun.io.useCanonCaches", false);
 useCanonPrefixCache = useCanonCaches && getBooleanProperty("sun.io.useCanonPrefixCache", false);
 }
}