jdk/src/share/classes/java/nio/file/Paths.java
changeset 2057 3acf8e5e2ca0
child 2072 80dfe4469bbd
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/share/classes/java/nio/file/Paths.java	Sun Feb 15 12:25:54 2009 +0000
@@ -0,0 +1,123 @@
+/*
+ * Copyright 2007-2009 Sun Microsystems, Inc.  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.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.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 class Paths {
+    private Paths() { }
+
+    /**
+     * Constructs a {@code Path} by converting the given path string.
+     *
+     * <p> The {@code Path} is obtained by invoking the {@link FileSystem#getPath
+     * getPath} method of the {@link FileSystems#getDefault default} {@link
+     * FileSystem}.
+     *
+     * @param   path
+     *          The path string to convert
+     *
+     * @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 path) {
+        return FileSystems.getDefault().getPath(path);
+    }
+
+    /**
+     * Converts the given URI to a {@link Path} object.
+     *
+     * <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><tt>
+     * Paths.get(</tt><i>p</i><tt>.{@link Path#toUri() toUri}()).equals(</tt>
+     * <i>p</i><tt>.{@link Path#toAbsolutePath() toAbsolutePath}())</tt>
+     * </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
+     *          If the file system identified by the URI does not exist 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");
+    }
+}