| /* | |
| * Copyright (c) 2007, 2023, 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. | |
| * {@snippet lang=java : | |
| * Set<PosixFilePermission> perms = PosixFilePermissions.fromString("rwxr-x---"); | |
| * } | |
| * | |
| * @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<>(perms); | |
| for (PosixFilePermission p: perms) { | |
| if (p == null) | |
| throw new NullPointerException(); | |
| } | |
| final Set<PosixFilePermission> value = perms; | |
| return new FileAttribute<>() { | |
| @Override | |
| public String name() { | |
| return "posix:permissions"; | |
| } | |
| @Override | |
| public Set<PosixFilePermission> value() { | |
| return Collections.unmodifiableSet(value); | |
| } | |
| }; | |
| } | |
| } |