| /* | |
| * Copyright (c) 2007, 2025, 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; | |
| import java.io.File; | |
| import java.io.IOException; | |
| import java.net.URI; | |
| import java.nio.file.spi.FileSystemProvider; | |
| import java.util.Iterator; | |
| import java.util.NoSuchElementException; | |
| import java.util.Objects; | |
| /** | |
| * An object that may be used to locate a file in a file system. It will | |
| * typically represent a system dependent file path. | |
| * | |
| * <p> A {@code Path} represents a path that is hierarchical and composed of a | |
| * sequence of directory and file name elements separated by a special separator | |
| * or delimiter. A <em>root component</em>, that identifies a file system | |
| * hierarchy, may also be present. The name element that is <em>farthest</em> | |
| * from the root of the directory hierarchy is the name of a file or directory. | |
| * The other name elements are directory names. A {@code Path} can represent a | |
| * root, a root and a sequence of names, or simply one or more name elements. | |
| * A {@code Path} is considered to be an <i>empty path</i> if it consists | |
| * solely of one name element that is empty. Accessing a file using an | |
| * <i>empty path</i> is equivalent to accessing the default directory of the | |
| * file system. {@code Path} defines the {@link #getFileName() getFileName}, | |
| * {@link #getParent getParent}, {@link #getRoot getRoot}, and {@link #subpath | |
| * subpath} methods to access the path components or a subsequence of its name | |
| * elements. | |
| * | |
| * <p> In addition to accessing the components of a path, a {@code Path} also | |
| * defines the {@link #resolve(Path) resolve} and {@link #resolveSibling(Path) | |
| * resolveSibling} methods to combine paths. The {@link #relativize relativize} | |
| * method that can be used to construct a relative path between two paths. | |
| * Paths can be {@link #compareTo compared}, and tested against each other using | |
| * the {@link #startsWith startsWith} and {@link #endsWith endsWith} methods. | |
| * | |
| * <p> This interface extends {@link Watchable} interface so that a directory | |
| * located by a path can be {@link #register registered} with a {@link | |
| * WatchService} and entries in the directory watched. </p> | |
| * | |
| * <p> <b>WARNING:</b> This interface is only intended to be implemented by | |
| * those developing custom file system implementations. Methods may be added to | |
| * this interface in future releases. </p> | |
| * | |
| * <h2>Accessing Files</h2> | |
| * <p> Paths may be used with the {@link Files} class to operate on files, | |
| * directories, and other types of files. For example, suppose we want a {@link | |
| * java.io.BufferedReader} to read text from a file "{@code access.log}". The | |
| * file is located in a directory "{@code logs}" relative to the current working | |
| * directory and is UTF-8 encoded. | |
| * {@snippet lang=java : | |
| * Path path = FileSystems.getDefault().getPath("logs", "access.log"); | |
| * BufferedReader reader = Files.newBufferedReader(path, StandardCharsets.UTF_8); | |
| * } | |
| * | |
| * <a id="interop"></a><h2>Interoperability</h2> | |
| * <p> Paths associated with the default {@link | |
| * java.nio.file.spi.FileSystemProvider provider} are generally interoperable | |
| * with the {@link java.io.File java.io.File} class. Paths created by other | |
| * providers are unlikely to be interoperable with the abstract path names | |
| * represented by {@code java.io.File}. The {@link java.io.File#toPath toPath} | |
| * method may be used to obtain a {@code Path} from the abstract path name | |
| * represented by a {@code java.io.File} object. The resulting {@code Path} can | |
| * be used to operate on the same file as the {@code java.io.File} object. In | |
| * addition, the {@link #toFile toFile} method is useful to construct a {@code | |
| * File} from the {@code String} representation of a {@code Path}. | |
| * | |
| * <h2>Concurrency</h2> | |
| * <p> Implementations of this interface are immutable and safe for use by | |
| * multiple concurrent threads. | |
| * | |
| * @since 1.7 | |
| */ | |
| public interface Path | |
| extends Comparable<Path>, Iterable<Path>, Watchable | |
| { | |
| /** | |
| * Returns a {@code Path} by converting a path string, or a sequence of | |
| * strings that when joined form a path string. If {@code more} does not | |
| * specify any elements then the value of the {@code first} parameter is | |
| * the path string to convert. If {@code more} specifies one or more | |
| * elements then each non-empty string, including {@code first}, is | |
| * considered to be a sequence of name elements and is joined to form a | |
| * path string. The details as to how the Strings are joined is provider | |
| * specific but typically they will be joined using the | |
| * {@link FileSystem#getSeparator name-separator} as the separator. | |
| * For example, if the name separator is "{@code /}" and | |
| * {@code getPath("/foo","bar","gus")} is invoked, then the path string | |
| * {@code "/foo/bar/gus"} is converted to a {@code Path}. A {@code Path} | |
| * representing an empty path is returned if {@code first} is the empty | |
| * string and {@code more} does not contain any non-empty strings. | |
| * | |
| * <p> The {@code Path} is obtained by invoking the {@link FileSystem#getPath | |
| * getPath} method of the {@link FileSystems#getDefault default} {@link | |
| * FileSystem}. | |
| * | |
| * <p> Note that while this method is very convenient, using it will imply | |
| * an assumed reference to the default {@code FileSystem} and limit the | |
| * utility of the calling code. Hence it should not be used in library code | |
| * intended for flexible reuse. A more flexible alternative is to use an | |
| * existing {@code Path} instance as an anchor, such as: | |
| * {@snippet lang=java : | |
| * Path dir = ... | |
| * Path path = dir.resolve("file"); | |
| * } | |
| * | |
| * @param first | |
| * the path string or initial part of the path string | |
| * @param more | |
| * additional strings to be joined to form the path string | |
| * | |
| * @return the resulting {@code Path} | |
| * | |
| * @throws InvalidPathException | |
| * if the path string cannot be converted to a {@code Path} | |
| * | |
| * @see FileSystem#getPath | |
| * | |
| * @since 11 | |
| */ | |
| public static Path of(String first, String... more) { | |
| return FileSystems.getDefault().getPath(first, more); | |
| } | |
| /** | |
| * Returns a {@code Path} by converting a URI. | |
| * | |
| * <p> This method iterates over the {@link FileSystemProvider#installedProviders() | |
| * installed} providers to locate the provider that is identified by the | |
| * URI {@link URI#getScheme scheme} of the given URI. URI schemes are | |
| * compared without regard to case. If the provider is found then its {@link | |
| * FileSystemProvider#getPath getPath} method is invoked to convert the | |
| * URI. | |
| * | |
| * <p> In the case of the default provider, identified by the URI scheme | |
| * "file", the given URI has a non-empty path component, and undefined query | |
| * and fragment components. Whether the authority component may be present | |
| * is platform specific. The returned {@code Path} is associated with the | |
| * {@link FileSystems#getDefault default} file system. | |
| * | |
| * <p> The default provider provides a similar <em>round-trip</em> guarantee | |
| * to the {@link java.io.File} class. For a given {@code Path} <i>p</i> it | |
| * is guaranteed that | |
| * <blockquote>{@code | |
| * Path.of(}<i>p</i>{@code .}{@link Path#toUri() toUri}{@code ()).equals(} | |
| * <i>p</i>{@code .}{@link Path#toAbsolutePath() toAbsolutePath}{@code ())} | |
| * </blockquote> | |
| * so long as the original {@code Path}, the {@code URI}, and the new {@code | |
| * Path} are all created in (possibly different invocations of) the same | |
| * Java virtual machine. Whether other providers make any guarantees is | |
| * provider specific and therefore unspecified. | |
| * | |
| * @param uri | |
| * the URI to convert | |
| * | |
| * @return the resulting {@code Path} | |
| * | |
| * @throws IllegalArgumentException | |
| * if preconditions on the {@code uri} parameter do not hold. The | |
| * format of the URI is provider specific. | |
| * @throws FileSystemNotFoundException | |
| * The file system, identified by the URI, does not exist and | |
| * cannot be created automatically, or the provider identified by | |
| * the URI's scheme component is not installed | |
| * | |
| * @since 11 | |
| */ | |
| public static Path of(URI uri) { | |
| String scheme = uri.getScheme(); | |
| if (scheme == null) | |
| throw new IllegalArgumentException("Missing scheme"); | |
| // check for default provider to avoid loading of installed providers | |
| if (scheme.equalsIgnoreCase("file")) | |
| return FileSystems.getDefault().provider().getPath(uri); | |
| // try to find provider | |
| for (FileSystemProvider provider: FileSystemProvider.installedProviders()) { | |
| if (provider.getScheme().equalsIgnoreCase(scheme)) { | |
| return provider.getPath(uri); | |
| } | |
| } | |
| throw new FileSystemNotFoundException("Provider \"" + scheme + "\" not installed"); | |
| } | |
| /** | |
| * Returns the file system that created this object. | |
| * | |
| * @return the file system that created this object | |
| */ | |
| FileSystem getFileSystem(); | |
| /** | |
| * Tells whether or not this path is absolute. | |
| * | |
| * <p> An absolute path is complete in that it doesn't need to be combined | |
| * with other path information in order to locate a file. | |
| * | |
| * @return {@code true} if, and only if, this path is absolute | |
| */ | |
| boolean isAbsolute(); | |
| /** | |
| * Returns the root component of this path as a {@code Path} object, | |
| * or {@code null} if this path does not have a root component. | |
| * | |
| * @return a path representing the root component of this path, | |
| * or {@code null} | |
| */ | |
| Path getRoot(); | |
| /** | |
| * Returns the name of the file or directory denoted by this path as a | |
| * {@code Path} object. The file name is the <em>farthest</em> element from | |
| * the root in the directory hierarchy. | |
| * | |
| * @return a path representing the name of the file or directory, or | |
| * {@code null} if this path has zero elements | |
| */ | |
| Path getFileName(); | |
| /** | |
| * Returns the <em>parent path</em>, or {@code null} if this path does not | |
| * have a parent. | |
| * | |
| * <p> The parent of this path object consists of this path's root | |
| * component, if any, and each element in the path except for the | |
| * <em>farthest</em> from the root in the directory hierarchy. This method | |
| * does not access the file system; the path or its parent may not exist. | |
| * Furthermore, this method does not eliminate special names such as "." | |
| * and ".." that may be used in some implementations. On UNIX for example, | |
| * the parent of "{@code /a/b/c}" is "{@code /a/b}", and the parent of | |
| * {@code "x/y/.}" is "{@code x/y}". This method may be used with the {@link | |
| * #normalize normalize} method, to eliminate redundant names, for cases where | |
| * <em>shell-like</em> navigation is required. | |
| * | |
| * <p> If this path has more than one element, and no root component, then | |
| * this method is equivalent to evaluating the expression: | |
| * {@snippet lang=java : | |
| * subpath(0, getNameCount()-1); | |
| * } | |
| * | |
| * @return a path representing the path's parent | |
| */ | |
| Path getParent(); | |
| /** | |
| * Returns the number of name elements in the path. | |
| * | |
| * @return the number of elements in the path, or {@code 0} if this path | |
| * only represents a root component | |
| */ | |
| int getNameCount(); | |
| /** | |
| * Returns a name element of this path as a {@code Path} object. | |
| * | |
| * <p> The {@code index} parameter is the index of the name element to return. | |
| * The element that is <em>closest</em> to the root in the directory hierarchy | |
| * has index {@code 0}. The element that is <em>farthest</em> from the root | |
| * has index {@link #getNameCount count}{@code -1}. | |
| * | |
| * @param index | |
| * the index of the element | |
| * | |
| * @return the name element | |
| * | |
| * @throws IllegalArgumentException | |
| * if {@code index} is negative, {@code index} is greater than or | |
| * equal to the number of elements, or this path has zero name | |
| * elements | |
| */ | |
| Path getName(int index); | |
| /** | |
| * Returns a relative {@code Path} that is a subsequence of the name | |
| * elements of this path. | |
| * | |
| * <p> The {@code beginIndex} and {@code endIndex} parameters specify the | |
| * subsequence of name elements. The name that is <em>closest</em> to the root | |
| * in the directory hierarchy has index {@code 0}. The name that is | |
| * <em>farthest</em> from the root has index {@link #getNameCount | |
| * count}{@code -1}. The returned {@code Path} object has the name elements | |
| * that begin at {@code beginIndex} and extend to the element at index {@code | |
| * endIndex-1}. | |
| * | |
| * @param beginIndex | |
| * the index of the first element, inclusive | |
| * @param endIndex | |
| * the index of the last element, exclusive | |
| * | |
| * @return a new {@code Path} object that is a subsequence of the name | |
| * elements in this {@code Path} | |
| * | |
| * @throws IllegalArgumentException | |
| * if {@code beginIndex} is negative, or greater than or equal to | |
| * the number of elements. If {@code endIndex} is less than or | |
| * equal to {@code beginIndex}, or larger than the number of elements. | |
| */ | |
| Path subpath(int beginIndex, int endIndex); | |
| /** | |
| * Tests if this path starts with the given path. | |
| * | |
| * <p> This path <em>starts</em> with the given path if this path's root | |
| * component <em>starts</em> with the root component of the given path, | |
| * and this path starts with the same name elements as the given path. | |
| * If the given path has more name elements than this path then {@code false} | |
| * is returned. | |
| * | |
| * <p> Whether or not the root component of this path starts with the root | |
| * component of the given path is file system specific. If this path does | |
| * not have a root component and the given path has a root component then | |
| * this path does not start with the given path. | |
| * | |
| * <p> If the given path is associated with a different {@code FileSystem} | |
| * to this path then {@code false} is returned. | |
| * | |
| * @param other | |
| * the given path | |
| * | |
| * @return {@code true} if this path starts with the given path; otherwise | |
| * {@code false} | |
| */ | |
| boolean startsWith(Path other); | |
| /** | |
| * Tests if this path starts with a {@code Path}, constructed by converting | |
| * the given path string, in exactly the manner specified by the {@link | |
| * #startsWith(Path) startsWith(Path)} method. On UNIX for example, the path | |
| * "{@code foo/bar}" starts with "{@code foo}" and "{@code foo/bar}". It | |
| * does not start with "{@code f}" or "{@code fo}". | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * startsWith(getFileSystem().getPath(other)); | |
| * } | |
| * | |
| * @param other | |
| * the given path string | |
| * | |
| * @return {@code true} if this path starts with the given path; otherwise | |
| * {@code false} | |
| * | |
| * @throws InvalidPathException | |
| * If the path string cannot be converted to a Path. | |
| */ | |
| default boolean startsWith(String other) { | |
| return startsWith(getFileSystem().getPath(other)); | |
| } | |
| /** | |
| * Tests if this path ends with the given path. | |
| * | |
| * <p> If the given path has <em>N</em> elements, and no root component, | |
| * and this path has <em>N</em> or more elements, then this path ends with | |
| * the given path if the last <em>N</em> elements of each path, starting at | |
| * the element farthest from the root, are equal. | |
| * | |
| * <p> If the given path has a root component then this path ends with the | |
| * given path if the root component of this path <em>ends with</em> the root | |
| * component of the given path, and the corresponding elements of both paths | |
| * are equal. Whether or not the root component of this path ends with the | |
| * root component of the given path is file system specific. If this path | |
| * does not have a root component and the given path has a root component | |
| * then this path does not end with the given path. | |
| * | |
| * <p> If the given path is associated with a different {@code FileSystem} | |
| * to this path then {@code false} is returned. | |
| * | |
| * @param other | |
| * the given path | |
| * | |
| * @return {@code true} if this path ends with the given path; otherwise | |
| * {@code false} | |
| */ | |
| boolean endsWith(Path other); | |
| /** | |
| * Tests if this path ends with a {@code Path}, constructed by converting | |
| * the given path string, in exactly the manner specified by the {@link | |
| * #endsWith(Path) endsWith(Path)} method. On UNIX for example, the path | |
| * "{@code foo/bar}" ends with "{@code foo/bar}" and "{@code bar}". It does | |
| * not end with "{@code r}" or "{@code /bar}". Note that trailing separators | |
| * are not taken into account, and so invoking this method on the {@code | |
| * Path} "{@code foo/bar}" with the {@code String} "{@code bar/}" returns | |
| * {@code true}. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * endsWith(getFileSystem().getPath(other)); | |
| * } | |
| * | |
| * @param other | |
| * the given path string | |
| * | |
| * @return {@code true} if this path ends with the given path; otherwise | |
| * {@code false} | |
| * | |
| * @throws InvalidPathException | |
| * If the path string cannot be converted to a Path. | |
| */ | |
| default boolean endsWith(String other) { | |
| return endsWith(getFileSystem().getPath(other)); | |
| } | |
| /** | |
| * Returns a path that is this path with redundant name elements eliminated. | |
| * | |
| * <p> The precise definition of this method is implementation dependent but | |
| * in general it derives from this path, a path that does not contain | |
| * <em>redundant</em> name elements. In many file systems, the "{@code .}" | |
| * and "{@code ..}" are special names used to indicate the current directory | |
| * and parent directory. In such file systems all occurrences of "{@code .}" | |
| * are considered redundant. If a "{@code ..}" is preceded by a | |
| * non-"{@code ..}" name then both names are considered redundant (the | |
| * process to identify such names is repeated until it is no longer | |
| * applicable). | |
| * | |
| * <p> This method does not access the file system; the path may not locate | |
| * a file that exists. Eliminating "{@code ..}" and a preceding name from a | |
| * path may result in the path that locates a different file than the original | |
| * path. This can arise when the preceding name is a symbolic link. | |
| * | |
| * @return the resulting path or this path if it does not contain | |
| * redundant name elements; an empty path is returned if this path | |
| * does not have a root component and all name elements are redundant | |
| * | |
| * @see #getParent | |
| * @see #toRealPath | |
| */ | |
| Path normalize(); | |
| // -- resolution and relativization -- | |
| /** | |
| * Resolve the given path against this path. | |
| * | |
| * <p> If the {@code other} parameter is an {@link #isAbsolute() absolute} | |
| * path then this method trivially returns {@code other}. If {@code other} | |
| * is an <i>empty path</i> then this method trivially returns this path. | |
| * Otherwise this method considers this path to be a directory and resolves | |
| * the given path against this path. In the simplest case, the given path | |
| * does not have a {@link #getRoot root} component, in which case this method | |
| * <em>joins</em> the given path to this path and returns a resulting path | |
| * that {@link #endsWith ends} with the given path. Where the given path has | |
| * a root component then resolution is highly implementation dependent and | |
| * therefore unspecified. | |
| * | |
| * @param other | |
| * the path to resolve against this path | |
| * | |
| * @return the resulting path | |
| * | |
| * @see #relativize | |
| */ | |
| Path resolve(Path other); | |
| /** | |
| * Converts a given path string to a {@code Path} and resolves it against | |
| * this {@code Path} in exactly the manner specified by the {@link | |
| * #resolve(Path) resolve} method. For example, suppose that the name | |
| * separator is "{@code /}" and a path represents "{@code foo/bar}", then | |
| * invoking this method with the path string "{@code gus}" will result in | |
| * the {@code Path} "{@code foo/bar/gus}". | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * resolve(getFileSystem().getPath(other)); | |
| * } | |
| * | |
| * @param other | |
| * the path string to resolve against this path | |
| * | |
| * @return the resulting path | |
| * | |
| * @throws InvalidPathException | |
| * if the path string cannot be converted to a Path. | |
| * | |
| * @see FileSystem#getPath | |
| */ | |
| default Path resolve(String other) { | |
| return resolve(getFileSystem().getPath(other)); | |
| } | |
| /** | |
| * Resolves a path against this path, and then iteratively resolves any | |
| * additional paths. | |
| * | |
| * <p> This method resolves {@code first} against this {@code Path} as if | |
| * by calling {@link #resolve(Path)}. If {@code more} has one or more | |
| * elements then it resolves the first element against the result, then | |
| * iteratively resolves all subsequent elements. This method returns the | |
| * result from the final resolve. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent to the result obtained with: | |
| * {@snippet lang=java : | |
| * Path result = resolve(first); | |
| * for (Path p : more) { | |
| * result = result.resolve(p); | |
| * } | |
| * } | |
| * | |
| * @param first | |
| * the first path to resolve against this path | |
| * @param more | |
| * additional paths to iteratively resolve | |
| * | |
| * @return the resulting path | |
| * | |
| * @see #resolve(Path) | |
| * @since 22 | |
| */ | |
| default Path resolve(Path first, Path... more) { | |
| Path result = resolve(first); | |
| for (Path p : more) { | |
| result = result.resolve(p); | |
| } | |
| return result; | |
| } | |
| /** | |
| * Converts a path string to a path, resolves that path against this path, | |
| * and then iteratively performs the same procedure for any additional | |
| * path strings. | |
| * | |
| * <p> This method converts {@code first} to a {@code Path} and resolves | |
| * that {@code Path} against this {@code Path} as if by calling | |
| * {@link #resolve(String)}. If {@code more} has one or more elements | |
| * then it converts the first element to a path, resolves that path against | |
| * the result, then iteratively converts and resolves all subsequent | |
| * elements. This method returns the result from the final resolve. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent to the result obtained with: | |
| * {@snippet lang=java : | |
| * Path result = resolve(first); | |
| * for (String s : more) { | |
| * result = result.resolve(s); | |
| * } | |
| * } | |
| * | |
| * @param first | |
| * the first path string to convert to a path and | |
| * resolve against this path | |
| * | |
| * @param more | |
| * additional path strings to be iteratively converted to | |
| * paths and resolved | |
| * | |
| * @return the resulting path | |
| * | |
| * @throws InvalidPathException | |
| * if a path string cannot be converted to a Path. | |
| * | |
| * @see #resolve(Path,Path...) | |
| * @see #resolve(String) | |
| * | |
| * @since 22 | |
| */ | |
| default Path resolve(String first, String... more) { | |
| Path result = resolve(first); | |
| for (String s : more) { | |
| result = result.resolve(s); | |
| } | |
| return result; | |
| } | |
| /** | |
| * Resolves the given path against this path's {@link #getParent parent} | |
| * path. This is useful where a file name needs to be <i>replaced</i> with | |
| * another file name. For example, suppose that the name separator is | |
| * "{@code /}" and a path represents "{@code dir1/dir2/foo}", then invoking | |
| * this method with the {@code Path} "{@code bar}" will result in the {@code | |
| * Path} "{@code dir1/dir2/bar}". If this path does not have a parent path, | |
| * or {@code other} is {@link #isAbsolute() absolute}, then this method | |
| * returns {@code other}. If {@code other} is an empty path then this method | |
| * returns this path's parent, or where this path doesn't have a parent, the | |
| * empty path. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * (getParent() == null) ? other : getParent().resolve(other); | |
| * } | |
| * unless {@code other == null}, in which case a | |
| * {@code NullPointerException} is thrown. | |
| * | |
| * @param other | |
| * the path to resolve against this path's parent | |
| * | |
| * @return the resulting path | |
| * | |
| * @see #resolve(Path) | |
| */ | |
| default Path resolveSibling(Path other) { | |
| if (other == null) | |
| throw new NullPointerException(); | |
| Path parent = getParent(); | |
| return (parent == null) ? other : parent.resolve(other); | |
| } | |
| /** | |
| * Converts a given path string to a {@code Path} and resolves it against | |
| * this path's {@link #getParent parent} path in exactly the manner | |
| * specified by the {@link #resolveSibling(Path) resolveSibling} method. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * resolveSibling(getFileSystem().getPath(other)); | |
| * } | |
| * | |
| * @param other | |
| * the path string to resolve against this path's parent | |
| * | |
| * @return the resulting path | |
| * | |
| * @throws InvalidPathException | |
| * if the path string cannot be converted to a Path. | |
| * | |
| * @see FileSystem#getPath | |
| */ | |
| default Path resolveSibling(String other) { | |
| return resolveSibling(getFileSystem().getPath(other)); | |
| } | |
| /** | |
| * Constructs a relative path between this path and a given path. | |
| * | |
| * <p> Relativization is the inverse of {@link #resolve(Path) resolution}. | |
| * This method attempts to construct a {@link #isAbsolute relative} path | |
| * that when {@link #resolve(Path) resolved} against this path, yields a | |
| * path that locates the same file as the given path. For example, on UNIX, | |
| * if this path is {@code "/a/b"} and the given path is {@code "/a/b/c/d"} | |
| * then the resulting relative path would be {@code "c/d"}. Where this | |
| * path and the given path do not have a {@link #getRoot root} component, | |
| * then a relative path can be constructed. A relative path cannot be | |
| * constructed if only one of the paths have a root component. Where both | |
| * paths have a root component then it is implementation dependent if a | |
| * relative path can be constructed. If this path and the given path are | |
| * {@link #equals equal} then an <i>empty path</i> is returned. | |
| * | |
| * <p> For any two {@link #normalize normalized} paths <i>p</i> and | |
| * <i>q</i>, where <i>q</i> does not have a root component, | |
| * <blockquote> | |
| * <i>p</i>{@code .relativize(}<i>p</i> | |
| * {@code .resolve(}<i>q</i>{@code )).equals(}<i>q</i>{@code )} | |
| * </blockquote> | |
| * | |
| * <p> When symbolic links are supported, then whether the resulting path, | |
| * when resolved against this path, yields a path that can be used to locate | |
| * the {@link Files#isSameFile same} file as {@code other} is implementation | |
| * dependent. For example, if this path is {@code "/a/b"} and the given | |
| * path is {@code "/a/x"} then the resulting relative path may be {@code | |
| * "../x"}. If {@code "b"} is a symbolic link then is implementation | |
| * dependent if {@code "a/b/../x"} would locate the same file as {@code "/a/x"}. | |
| * | |
| * @param other | |
| * the path to relativize against this path | |
| * | |
| * @return the resulting relative path, or an empty path if both paths are | |
| * equal | |
| * | |
| * @throws IllegalArgumentException | |
| * if {@code other} is not a {@code Path} that can be relativized | |
| * against this path | |
| */ | |
| Path relativize(Path other); | |
| /** | |
| * Returns a URI to represent this path. | |
| * | |
| * <p> This method constructs an absolute {@link URI} with a {@link | |
| * URI#getScheme() scheme} equal to the URI scheme that identifies the | |
| * provider. The exact form of the scheme specific part is highly provider | |
| * dependent. | |
| * | |
| * <p> In the case of the default provider, the URI is hierarchical with | |
| * a {@link URI#getPath() path} component that is absolute. The query and | |
| * fragment components are undefined. Whether the authority component is | |
| * defined or not is implementation dependent. There is no guarantee that | |
| * the {@code URI} may be used to construct a {@link java.io.File java.io.File}. | |
| * In particular, if this path represents a Universal Naming Convention (UNC) | |
| * path, then the UNC server name may be encoded in the authority component | |
| * of the resulting URI. In the case of the default provider, and the file | |
| * exists, and it can be determined that the file is a directory, then the | |
| * resulting {@code URI} will end with a slash. | |
| * | |
| * <p> The default provider provides a similar <em>round-trip</em> guarantee | |
| * to the {@link java.io.File} class. For a given {@code Path} <i>p</i> it | |
| * is guaranteed that | |
| * <blockquote> | |
| * {@link Path#of(URI) Path.of}{@code (}<i>p</i>{@code .toUri()).equals(}<i>p</i> | |
| * {@code .}{@link #toAbsolutePath() toAbsolutePath}{@code ())} | |
| * </blockquote> | |
| * so long as the original {@code Path}, the {@code URI}, and the new {@code | |
| * Path} are all created in (possibly different invocations of) the same | |
| * Java virtual machine. Whether other providers make any guarantees is | |
| * provider specific and therefore unspecified. | |
| * | |
| * <p> When a file system is constructed to access the contents of a file | |
| * as a file system then it is highly implementation specific if the returned | |
| * URI represents the given path in the file system or it represents a | |
| * <em>compound</em> URI that encodes the URI of the enclosing file system. | |
| * A format for compound URIs is not defined in this release; such a scheme | |
| * may be added in a future release. | |
| * | |
| * @return the URI representing this path | |
| * | |
| * @throws java.io.IOError | |
| * if an I/O error occurs obtaining the absolute path, or where a | |
| * file system is constructed to access the contents of a file as | |
| * a file system, and the URI of the enclosing file system cannot be | |
| * obtained | |
| */ | |
| URI toUri(); | |
| /** | |
| * Returns a {@code Path} object representing the absolute path of this | |
| * path. Where this {@code Path} is associated with the default provider, | |
| * then the returned absolute path will have a non-{@code null} | |
| * {@linkplain #getRoot root component}. | |
| * | |
| * <p> If this path is already {@link Path#isAbsolute absolute} then this | |
| * method simply returns this path. Otherwise, this method resolves the path | |
| * in an implementation dependent manner, typically by resolving the path | |
| * against a file system default directory. Depending on the implementation, | |
| * this method may throw an I/O error if the file system is not accessible. | |
| * | |
| * @return a {@code Path} object representing the absolute path | |
| * | |
| * @throws java.io.IOError | |
| * if an I/O error occurs | |
| */ | |
| Path toAbsolutePath(); | |
| /** | |
| * Returns the <em>real</em> path of an existing file. | |
| * | |
| * <p> The precise definition of this method is implementation dependent but | |
| * in general it derives from this path, an {@link #isAbsolute absolute} | |
| * path that locates the {@link Files#isSameFile same} file as this path, but | |
| * with name elements that represent the actual name of the directories | |
| * and the file. For example, where filename comparisons on a file system | |
| * are case insensitive then the name elements represent the names in their | |
| * actual case. Additionally, the resulting path has redundant name | |
| * elements removed. | |
| * | |
| * <p> If this path is relative then its absolute path is first obtained, | |
| * as if by invoking the {@link #toAbsolutePath toAbsolutePath} method. | |
| * | |
| * <p> The {@code options} array may be used to indicate how symbolic links | |
| * are handled. By default, symbolic links are resolved to their final | |
| * target. If the option {@link LinkOption#NOFOLLOW_LINKS NOFOLLOW_LINKS} is | |
| * present then this method does not resolve symbolic links. | |
| * | |
| * Some implementations allow special names such as "{@code ..}" to refer to | |
| * the parent directory. When deriving the <em>real path</em>, and a | |
| * "{@code ..}" (or equivalent) is preceded by a non-"{@code ..}" name then | |
| * an implementation will typically cause both names to be removed. When | |
| * not resolving symbolic links and the preceding name is a symbolic link | |
| * then the names are only removed if it is guaranteed that the resulting | |
| * path will locate the same file as this path. | |
| * | |
| * @param options | |
| * options indicating how symbolic links are handled | |
| * | |
| * @return an absolute path represent the <em>real</em> path of the file | |
| * located by this object | |
| * | |
| * @throws IOException | |
| * if the file does not exist or an I/O error occurs | |
| */ | |
| Path toRealPath(LinkOption... options) throws IOException; | |
| /** | |
| * Returns a {@link File} object representing this path. Where this {@code | |
| * Path} is associated with the default provider, then this method is | |
| * equivalent to returning a {@code File} object constructed with the | |
| * {@code String} representation of this path. | |
| * | |
| * <p> If this path was created by invoking the {@code File} {@link | |
| * File#toPath toPath} method then there is no guarantee that the {@code | |
| * File} object returned by this method is {@link #equals equal} to the | |
| * original {@code File}. | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * new File(toString()); | |
| * } | |
| * if the {@code FileSystem} which created this {@code Path} is the default | |
| * file system; otherwise an {@code UnsupportedOperationException} is | |
| * thrown. | |
| * | |
| * @return a {@code File} object representing this path | |
| * | |
| * @throws UnsupportedOperationException | |
| * if this {@code Path} is not associated with the default provider | |
| */ | |
| default File toFile() { | |
| if (getFileSystem() == FileSystems.getDefault()) { | |
| return new File(toString()); | |
| } else { | |
| throw new UnsupportedOperationException("Path not associated with " | |
| + "default file system."); | |
| } | |
| } | |
| // -- watchable -- | |
| /** | |
| * Registers the file located by this path with a watch service. | |
| * | |
| * <p> In this release, this path locates a directory that exists. The | |
| * directory is registered with the watch service so that entries in the | |
| * directory can be watched. The {@code events} parameter is the events to | |
| * register and may contain the following events: | |
| * <ul> | |
| * <li>{@link StandardWatchEventKinds#ENTRY_CREATE ENTRY_CREATE} - | |
| * entry created or moved into the directory</li> | |
| * <li>{@link StandardWatchEventKinds#ENTRY_DELETE ENTRY_DELETE} - | |
| * entry deleted or moved out of the directory</li> | |
| * <li>{@link StandardWatchEventKinds#ENTRY_MODIFY ENTRY_MODIFY} - | |
| * entry in directory was modified</li> | |
| * </ul> | |
| * | |
| * <p> The {@link WatchEvent#context context} for these events is the | |
| * relative path between the directory located by this path, and the path | |
| * that locates the directory entry that is created, deleted, or modified. | |
| * | |
| * <p> The set of events may include additional implementation specific | |
| * event that are not defined by the enum {@link StandardWatchEventKinds} | |
| * | |
| * <p> The {@code modifiers} parameter specifies <em>modifiers</em> that | |
| * qualify how the directory is registered. This release does not define any | |
| * <em>standard</em> modifiers. It may contain implementation specific | |
| * modifiers. | |
| * | |
| * <p> Where a file is registered with a watch service by means of a symbolic | |
| * link then it is implementation specific if the watch continues to depend | |
| * on the existence of the symbolic link after it is registered. | |
| * | |
| * @param watcher | |
| * the watch service to which this object is to be registered | |
| * @param events | |
| * the events for which this object should be registered | |
| * @param modifiers | |
| * the modifiers, if any, that modify how the object is registered | |
| * | |
| * @return a key representing the registration of this object with the | |
| * given watch service | |
| * | |
| * @throws UnsupportedOperationException | |
| * if unsupported events or modifiers are specified | |
| * @throws IllegalArgumentException | |
| * if an invalid combination of events or modifiers is specified | |
| * @throws ClosedWatchServiceException | |
| * if the watch service is closed | |
| * @throws NotDirectoryException | |
| * if the file is registered to watch the entries in a directory | |
| * and the file is not a directory <i>(optional specific exception)</i> | |
| * @throws IOException | |
| * if an I/O error occurs | |
| */ | |
| @Override | |
| WatchKey register(WatchService watcher, | |
| WatchEvent.Kind<?>[] events, | |
| WatchEvent.Modifier... modifiers) | |
| throws IOException; | |
| /** | |
| * Registers the file located by this path with a watch service. | |
| * | |
| * <p> An invocation of this method behaves in exactly the same way as the | |
| * invocation | |
| * {@snippet lang=java : | |
| * // @link substring="register" target="Watchable#register" : | |
| * register(watcher, events, new WatchEvent.Modifier[0]); | |
| * } | |
| * | |
| * <p> <b>Usage Example:</b> | |
| * Suppose we wish to register a directory for entry create, delete, and modify | |
| * events: | |
| * {@snippet lang=java : | |
| * Path dir = ... | |
| * WatchService watcher = ... | |
| * | |
| * WatchKey key = dir.register(watcher, ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY); | |
| * } | |
| * | |
| * @implSpec | |
| * The default implementation is equivalent for this path to: | |
| * {@snippet lang=java : | |
| * register(watcher, events, new WatchEvent.Modifier[0]); | |
| * } | |
| * | |
| * @param watcher | |
| * The watch service to which this object is to be registered | |
| * @param events | |
| * The events for which this object should be registered | |
| * | |
| * @return A key representing the registration of this object with the | |
| * given watch service | |
| * | |
| * @throws UnsupportedOperationException | |
| * If unsupported events are specified | |
| * @throws IllegalArgumentException | |
| * If an invalid combination of events is specified | |
| * @throws ClosedWatchServiceException | |
| * If the watch service is closed | |
| * @throws NotDirectoryException | |
| * If the file is registered to watch the entries in a directory | |
| * and the file is not a directory <i>(optional specific exception)</i> | |
| * @throws IOException | |
| * If an I/O error occurs | |
| */ | |
| @Override | |
| default WatchKey register(WatchService watcher, | |
| WatchEvent.Kind<?>... events) throws IOException { | |
| return register(watcher, events, new WatchEvent.Modifier[0]); | |
| } | |
| // -- Iterable -- | |
| /** | |
| * Returns an iterator over the name elements of this path. | |
| * | |
| * <p> The first element returned by the iterator represents the name | |
| * element that is closest to the root in the directory hierarchy, the | |
| * second element is the next closest, and so on. The last element returned | |
| * is the name of the file or directory denoted by this path. The {@link | |
| * #getRoot root} component, if present, is not returned by the iterator. | |
| * | |
| * @implSpec | |
| * The default implementation returns an {@code Iterator<Path>} which, for | |
| * this path, traverses the {@code Path}s returned by | |
| * {@code getName(index)}, where {@code index} ranges from zero to | |
| * {@code getNameCount() - 1}, inclusive. | |
| * | |
| * @return an iterator over the name elements of this path | |
| */ | |
| @Override | |
| default Iterator<Path> iterator() { | |
| return new Iterator<>() { | |
| private int i = 0; | |
| @Override | |
| public boolean hasNext() { | |
| return (i < getNameCount()); | |
| } | |
| @Override | |
| public Path next() { | |
| if (i < getNameCount()) { | |
| Path result = getName(i); | |
| i++; | |
| return result; | |
| } else { | |
| throw new NoSuchElementException(); | |
| } | |
| } | |
| }; | |
| } | |
| // -- compareTo/equals/hashCode -- | |
| /** | |
| * Compares two abstract paths lexicographically. The ordering defined by | |
| * this method is provider specific, and in the case of the default | |
| * provider, platform specific. This method does not access the file system | |
| * and neither file is required to exist. | |
| * | |
| * <p> This method may not be used to compare paths that are associated | |
| * with different file system providers. | |
| * | |
| * @param other the path compared to this path. | |
| * | |
| * @return zero if the argument is {@link #equals equal} to this path, a | |
| * value less than zero if this path is lexicographically less than | |
| * the argument, or a value greater than zero if this path is | |
| * lexicographically greater than the argument | |
| * | |
| * @throws ClassCastException | |
| * if the paths are associated with different providers | |
| */ | |
| @Override | |
| int compareTo(Path other); | |
| /** | |
| * Tests this path for equality with the given object. | |
| * | |
| * <p> If the given object is not a Path, or is a Path associated with a | |
| * different {@code FileSystem}, then this method returns {@code false}. | |
| * | |
| * <p> Whether or not two path are equal depends on the file system | |
| * implementation. In some cases the paths are compared without regard | |
| * to case, and others are case sensitive. This method does not access the | |
| * file system and the file is not required to exist. Where required, the | |
| * {@link Files#isSameFile isSameFile} method may be used to check if two | |
| * paths locate the same file. | |
| * | |
| * <p> This method satisfies the general contract of the {@link | |
| * java.lang.Object#equals(Object) Object.equals} method. </p> | |
| * | |
| * @param other | |
| * the object to which this object is to be compared | |
| * | |
| * @return {@code true} if, and only if, the given object is a {@code Path} | |
| * that is identical to this {@code Path} | |
| */ | |
| @Override | |
| boolean equals(Object other); | |
| /** | |
| * Computes a hash code for this path. | |
| * | |
| * <p> The hash code is based upon the components of the path, and | |
| * satisfies the general contract of the {@link Object#hashCode | |
| * Object.hashCode} method. | |
| * | |
| * @return the hash-code value for this path | |
| */ | |
| @Override | |
| int hashCode(); | |
| /** | |
| * {@return the string representation of this path} | |
| * | |
| * <p> If this path was created by converting a path string using the | |
| * {@link FileSystem#getPath getPath} method then the path string returned | |
| * by this method may differ from the original String used to create the path. | |
| * | |
| * <p> The returned path string uses the default name {@link | |
| * FileSystem#getSeparator separator} to separate names in the path. | |
| */ | |
| @Override | |
| String toString(); | |
| } |