8187443: Forest Consolidation: Move files to unified layout

Reviewed-by: darcy, ihse

src/java.base/share/classes/sun/nio/fs/AbstractFileSystemProvider.java

@@ -0,0 +1,157 @@
+/*
+ * Copyright (c) 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 sun.nio.fs;
+
+import java.nio.file.Path;
+import java.nio.file.LinkOption;
+import java.nio.file.attribute.BasicFileAttributes;
+import java.nio.file.spi.FileSystemProvider;
+import java.io.IOException;
+import java.util.Map;
+
+/**
+ * Base implementation class of FileSystemProvider
+ */
+
+public abstract class AbstractFileSystemProvider extends FileSystemProvider {
+    protected AbstractFileSystemProvider() { }
+
+    /**
+     * Splits the given attribute name into the name of an attribute view and
+     * the attribute. If the attribute view is not identified then it assumed
+     * to be "basic".
+     */
+    private static String[] split(String attribute) {
+        String[] s = new String[2];
+        int pos = attribute.indexOf(':');
+        if (pos == -1) {
+            s[0] = "basic";
+            s[1] = attribute;
+        } else {
+            s[0] = attribute.substring(0, pos++);
+            s[1] = (pos == attribute.length()) ? "" : attribute.substring(pos);
+        }
+        return s;
+    }
+
+    /**
+     * Gets a DynamicFileAttributeView by name. Returns {@code null} if the
+     * view is not available.
+     */
+    abstract DynamicFileAttributeView getFileAttributeView(Path file,
+                                                           String name,
+                                                           LinkOption... options);
+
+    @Override
+    public final void setAttribute(Path file,
+                                   String attribute,
+                                   Object value,
+                                   LinkOption... options)
+        throws IOException
+    {
+        String[] s = split(attribute);
+        if (s[0].length() == 0)
+            throw new IllegalArgumentException(attribute);
+        DynamicFileAttributeView view = getFileAttributeView(file, s[0], options);
+        if (view == null)
+            throw new UnsupportedOperationException("View '" + s[0] + "' not available");
+        view.setAttribute(s[1], value);
+    }
+
+    @Override
+    public final Map<String,Object> readAttributes(Path file, String attributes, LinkOption... options)
+        throws IOException
+    {
+        String[] s = split(attributes);
+        if (s[0].length() == 0)
+            throw new IllegalArgumentException(attributes);
+        DynamicFileAttributeView view = getFileAttributeView(file, s[0], options);
+        if (view == null)
+            throw new UnsupportedOperationException("View '" + s[0] + "' not available");
+        return view.readAttributes(s[1].split(","));
+    }
+
+    /**
+     * Deletes a file. The {@code failIfNotExists} parameters determines if an
+     * {@code IOException} is thrown when the file does not exist.
+     */
+    abstract boolean implDelete(Path file, boolean failIfNotExists) throws IOException;
+
+    @Override
+    public final void delete(Path file) throws IOException {
+        implDelete(file, true);
+    }
+
+    @Override
+    public final boolean deleteIfExists(Path file) throws IOException {
+        return implDelete(file, false);
+    }
+
+    /**
+     * Tests whether a file is a directory.
+     *
+     * @return  {@code true} if the file is a directory; {@code false} if
+     *          the file does not exist, is not a directory, or it cannot
+     *          be determined if the file is a directory or not.
+     */
+    public boolean isDirectory(Path file) {
+        try {
+            return readAttributes(file, BasicFileAttributes.class).isDirectory();
+        } catch (IOException ioe) {
+            return false;
+        }
+    }
+
+    /**
+     * Tests whether a file is a regular file with opaque content.
+     *
+     * @return  {@code true} if the file is a regular file; {@code false} if
+     *          the file does not exist, is not a regular file, or it
+     *          cannot be determined if the file is a regular file or not.
+     */
+    public boolean isRegularFile(Path file) {
+        try {
+            return readAttributes(file, BasicFileAttributes.class).isRegularFile();
+        } catch (IOException ioe) {
+            return false;
+        }
+    }
+
+    /**
+     * Checks the existence of a file.
+     *
+     * @return  {@code true} if the file exists; {@code false} if the file does
+     *          not exist or its existence cannot be determined.
+     */
+    public boolean exists(Path file) {
+        try {
+            checkAccess(file);
+            return true;
+        } catch (IOException ioe) {
+            return false;
+        }
+    }
+}