| /* |
| * Copyright 2013 Google Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package com.google.common.jimfs; |
| |
| import static com.google.common.base.Preconditions.checkNotNull; |
| import static com.google.common.base.Preconditions.checkState; |
| |
| import com.google.common.base.MoreObjects; |
| import java.nio.file.FileAlreadyExistsException; |
| import java.nio.file.NoSuchFileException; |
| import java.nio.file.NotDirectoryException; |
| import java.nio.file.NotLinkException; |
| import java.nio.file.Path; |
| import java.util.Objects; |
| import org.checkerframework.checker.nullness.compatqual.NullableDecl; |
| |
| /** |
| * Entry in a directory, containing references to the directory itself, the file the entry links to |
| * and the name of the entry. |
| * |
| * <p>May also represent a non-existent entry if the name does not link to any file in the |
| * directory. |
| */ |
| final class DirectoryEntry { |
| |
| private final Directory directory; |
| private final Name name; |
| |
| @NullableDecl private final File file; |
| |
| @NullableDecl DirectoryEntry next; // for use in Directory |
| |
| DirectoryEntry(Directory directory, Name name, @NullableDecl File file) { |
| this.directory = checkNotNull(directory); |
| this.name = checkNotNull(name); |
| this.file = file; |
| } |
| |
| /** Returns {@code true} if and only if this entry represents an existing file. */ |
| public boolean exists() { |
| return file != null; |
| } |
| |
| /** |
| * Checks that this entry exists, throwing an exception if not. |
| * |
| * @return this |
| * @throws NoSuchFileException if this entry does not exist |
| */ |
| public DirectoryEntry requireExists(Path pathForException) throws NoSuchFileException { |
| if (!exists()) { |
| throw new NoSuchFileException(pathForException.toString()); |
| } |
| return this; |
| } |
| |
| /** |
| * Checks that this entry does not exist, throwing an exception if it does. |
| * |
| * @return this |
| * @throws FileAlreadyExistsException if this entry does not exist |
| */ |
| public DirectoryEntry requireDoesNotExist(Path pathForException) |
| throws FileAlreadyExistsException { |
| if (exists()) { |
| throw new FileAlreadyExistsException(pathForException.toString()); |
| } |
| return this; |
| } |
| |
| /** |
| * Checks that this entry exists and links to a directory, throwing an exception if not. |
| * |
| * @return this |
| * @throws NoSuchFileException if this entry does not exist |
| * @throws NotDirectoryException if this entry does not link to a directory |
| */ |
| public DirectoryEntry requireDirectory(Path pathForException) |
| throws NoSuchFileException, NotDirectoryException { |
| requireExists(pathForException); |
| if (!file().isDirectory()) { |
| throw new NotDirectoryException(pathForException.toString()); |
| } |
| return this; |
| } |
| |
| /** |
| * Checks that this entry exists and links to a symbolic link, throwing an exception if not. |
| * |
| * @return this |
| * @throws NoSuchFileException if this entry does not exist |
| * @throws NotLinkException if this entry does not link to a symbolic link |
| */ |
| public DirectoryEntry requireSymbolicLink(Path pathForException) |
| throws NoSuchFileException, NotLinkException { |
| requireExists(pathForException); |
| if (!file().isSymbolicLink()) { |
| throw new NotLinkException(pathForException.toString()); |
| } |
| return this; |
| } |
| |
| /** Returns the directory containing this entry. */ |
| public Directory directory() { |
| return directory; |
| } |
| |
| /** Returns the name of this entry. */ |
| public Name name() { |
| return name; |
| } |
| |
| /** |
| * Returns the file this entry links to. |
| * |
| * @throws IllegalStateException if the file does not exist |
| */ |
| public File file() { |
| checkState(exists()); |
| return file; |
| } |
| |
| /** Returns the file this entry links to or {@code null} if the file does not exist */ |
| @NullableDecl |
| public File fileOrNull() { |
| return file; |
| } |
| |
| @Override |
| public boolean equals(Object obj) { |
| if (obj instanceof DirectoryEntry) { |
| DirectoryEntry other = (DirectoryEntry) obj; |
| return directory.equals(other.directory) |
| && name.equals(other.name) |
| && Objects.equals(file, other.file); |
| } |
| return false; |
| } |
| |
| @Override |
| public int hashCode() { |
| return Objects.hash(directory, name, file); |
| } |
| |
| @Override |
| public String toString() { |
| return MoreObjects.toStringHelper(this) |
| .add("directory", directory) |
| .add("name", name) |
| .add("file", file) |
| .toString(); |
| } |
| } |