/* * 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; import java.nio.file.spi.FileSystemProvider; import java.net.URI; /** * This class consists exclusively of static methods that return a {@link Path} * by converting a path string or {@link URI}. * * @since 1.7 */ public final class Paths { private Paths() { } /** * Converts a path string, or a sequence of strings that when joined form * a path string, to a {@code Path}. 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 (see {@link Path}) 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. * *

The {@code Path} is obtained by invoking the {@link FileSystem#getPath * getPath} method of the {@link FileSystems#getDefault default} {@link * FileSystem}. * *

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: * 

     *     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 */ public static Path get(String first, String... more) { return FileSystems.getDefault().getPath(first, more); } /** * Converts the given URI to a {@link Path} object. * *

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. * *

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. * *

The default provider provides a similar round-trip guarantee * to the {@link java.io.File} class. For a given {@code Path} p it * is guaranteed that *

* Paths.get(p.{@link Path#toUri() toUri}()).equals( * p.{@link Path#toAbsolutePath() toAbsolutePath}()) *
* 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 * @throws SecurityException * if a security manager is installed and it denies an unspecified * permission to access the file system */ public static Path get(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"); } }