| /* |
| * Copyright (c) 2007, 2011, 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 static java.nio.file.attribute.PosixFilePermission.*; |
| import java.util.*; |
| |
| /** |
| * This class consists exclusively of static methods that operate on sets of |
| * {@link PosixFilePermission} objects. |
| * |
| * @since 1.7 |
| */ |
| |
| public final class PosixFilePermissions { |
| private PosixFilePermissions() { } |
| |
| // Write string representation of permission bits to {@code sb}. |
| private static void writeBits(StringBuilder sb, boolean r, boolean w, boolean x) { |
| if (r) { |
| sb.append('r'); |
| } else { |
| sb.append('-'); |
| } |
| if (w) { |
| sb.append('w'); |
| } else { |
| sb.append('-'); |
| } |
| if (x) { |
| sb.append('x'); |
| } else { |
| sb.append('-'); |
| } |
| } |
| |
| /** |
| * Returns the {@code String} representation of a set of permissions. It |
| * is guaranteed that the returned {@code String} can be parsed by the |
| * {@link #fromString} method. |
| * |
| * <p> If the set contains {@code null} or elements that are not of type |
| * {@code PosixFilePermission} then these elements are ignored. |
| * |
| * @param perms |
| * the set of permissions |
| * |
| * @return the string representation of the permission set |
| */ |
| public static String toString(Set<PosixFilePermission> perms) { |
| StringBuilder sb = new StringBuilder(9); |
| writeBits(sb, perms.contains(OWNER_READ), perms.contains(OWNER_WRITE), |
| perms.contains(OWNER_EXECUTE)); |
| writeBits(sb, perms.contains(GROUP_READ), perms.contains(GROUP_WRITE), |
| perms.contains(GROUP_EXECUTE)); |
| writeBits(sb, perms.contains(OTHERS_READ), perms.contains(OTHERS_WRITE), |
| perms.contains(OTHERS_EXECUTE)); |
| return sb.toString(); |
| } |
| |
| private static boolean isSet(char c, char setValue) { |
| if (c == setValue) |
| return true; |
| if (c == '-') |
| return false; |
| throw new IllegalArgumentException("Invalid mode"); |
| } |
| private static boolean isR(char c) { return isSet(c, 'r'); } |
| private static boolean isW(char c) { return isSet(c, 'w'); } |
| private static boolean isX(char c) { return isSet(c, 'x'); } |
| |
| /** |
| * Returns the set of permissions corresponding to a given {@code String} |
| * representation. |
| * |
| * <p> The {@code perms} parameter is a {@code String} representing the |
| * permissions. It has 9 characters that are interpreted as three sets of |
| * three. The first set refers to the owner's permissions; the next to the |
| * group permissions and the last to others. Within each set, the first |
| * character is {@code 'r'} to indicate permission to read, the second |
| * character is {@code 'w'} to indicate permission to write, and the third |
| * character is {@code 'x'} for execute permission. Where a permission is |
| * not set then the corresponding character is set to {@code '-'}. |
| * |
| * <p> <b>Usage Example:</b> |
| * Suppose we require the set of permissions that indicate the owner has read, |
| * write, and execute permissions, the group has read and execute permissions |
| * and others have none. |
| * <pre> |
| * Set<PosixFilePermission> perms = PosixFilePermissions.fromString("rwxr-x---"); |
| * </pre> |
| * |
| * @param perms |
| * string representing a set of permissions |
| * |
| * @return the resulting set of permissions |
| * |
| * @throws IllegalArgumentException |
| * if the string cannot be converted to a set of permissions |
| * |
| * @see #toString(Set) |
| */ |
| public static Set<PosixFilePermission> fromString(String perms) { |
| if (perms.length() != 9) |
| throw new IllegalArgumentException("Invalid mode"); |
| Set<PosixFilePermission> result = EnumSet.noneOf(PosixFilePermission.class); |
| if (isR(perms.charAt(0))) result.add(OWNER_READ); |
| if (isW(perms.charAt(1))) result.add(OWNER_WRITE); |
| if (isX(perms.charAt(2))) result.add(OWNER_EXECUTE); |
| if (isR(perms.charAt(3))) result.add(GROUP_READ); |
| if (isW(perms.charAt(4))) result.add(GROUP_WRITE); |
| if (isX(perms.charAt(5))) result.add(GROUP_EXECUTE); |
| if (isR(perms.charAt(6))) result.add(OTHERS_READ); |
| if (isW(perms.charAt(7))) result.add(OTHERS_WRITE); |
| if (isX(perms.charAt(8))) result.add(OTHERS_EXECUTE); |
| return result; |
| } |
| |
| /** |
| * Creates a {@link FileAttribute}, encapsulating a copy of the given file |
| * permissions, suitable for passing to the {@link java.nio.file.Files#createFile |
| * createFile} or {@link java.nio.file.Files#createDirectory createDirectory} |
| * methods. |
| * |
| * @param perms |
| * the set of permissions |
| * |
| * @return an attribute encapsulating the given file permissions with |
| * {@link FileAttribute#name name} {@code "posix:permissions"} |
| * |
| * @throws ClassCastException |
| * if the set contains elements that are not of type {@code |
| * PosixFilePermission} |
| */ |
| public static FileAttribute<Set<PosixFilePermission>> |
| asFileAttribute(Set<PosixFilePermission> perms) |
| { |
| // copy set and check for nulls (CCE will be thrown if an element is not |
| // a PosixFilePermission) |
| perms = new HashSet<PosixFilePermission>(perms); |
| for (PosixFilePermission p: perms) { |
| if (p == null) |
| throw new NullPointerException(); |
| } |
| final Set<PosixFilePermission> value = perms; |
| return new FileAttribute<Set<PosixFilePermission>>() { |
| @Override |
| public String name() { |
| return "posix:permissions"; |
| } |
| @Override |
| public Set<PosixFilePermission> value() { |
| return Collections.unmodifiableSet(value); |
| } |
| }; |
| } |
| } |
