--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/nio/file/Files/CreateFileTree.java	Sun Feb 15 12:25:54 2009 +0000
@@ -0,0 +1,96 @@
+/*
+ * Copyright 2008-2009 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.
+ *
+ * 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.
+ */
+
+import java.nio.file.*;
+import java.io.IOException;
+import java.util.*;
+
+/**
+ * Creates a file tree with possible cycles caused by symbolic links
+ * to ancestor directories.
+ */
+
+public class CreateFileTree {
+
+    static final Random rand = new Random();
+
+    public static Path createTemporaryDirectory() throws IOException {
+        Path tmpdir = Paths.get(System.getProperty("java.io.tmpdir"));
+        Path dir;
+        do {
+            dir = tmpdir.resolve("name" + rand.nextInt());
+        } while (dir.exists());
+        dir.createDirectory();
+        return dir;
+    }
+
+    public static void main(String[] args) throws IOException {
+        Path top = createTemporaryDirectory();
+        if (!top.isAbsolute())
+            top = top.toAbsolutePath();
+
+        List<Path> dirs = new ArrayList<Path>();
+
+        // create tree
+        Queue<Path> queue = new ArrayDeque<Path>();
+        queue.add(top);
+        int total = 1 + rand.nextInt(20);
+        int n = 0;
+        Path dir;
+        while (((dir = queue.poll()) != null) && (n < total)) {
+            int r = Math.min((total-n), (1+rand.nextInt(3)));
+            for (int i=0; i<r; i++) {
+                String name = "dir" + (++n);
+                Path subdir = dir.resolve(name).createDirectory();
+                queue.offer(subdir);
+                dirs.add(subdir);
+            }
+        }
+        assert dirs.size() >= 2;
+
+        // create a few regular files in the file tree
+        int files = dirs.size() * 3;
+        for (int i=0; i<files; i++) {
+            String name = "file" + (i+1);
+            int x = rand.nextInt(dirs.size());
+            dirs.get(x).resolve(name).createFile();
+        }
+
+        // create a few sym links in the file tree so as to create cycles
+        int links = 1 + rand.nextInt(5);
+        for (int i=0; i<links; i++) {
+            int x = rand.nextInt(dirs.size());
+            int y;
+            do {
+                y = rand.nextInt(dirs.size());
+            } while (y != x);
+            String name = "link" + (i+1);
+            Path link = dirs.get(x).resolve(name);
+            Path target = dirs.get(y);
+            link.createSymbolicLink(target);
+        }
+
+        // done
+        System.out.println(top);
+    }
+}