diff -r 44a96761a7bc openide.filesystems/test/unit/src/org/openide/filesystems/MutilFileSystemLayeredDeliveryTest.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/openide.filesystems/test/unit/src/org/openide/filesystems/MutilFileSystemLayeredDeliveryTest.java	Wed Sep 16 09:25:25 2009 +0200
@@ -0,0 +1,162 @@
+/*
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
+ *
+ * Copyright 1997-2007 Sun Microsystems, Inc. All rights reserved.
+ *
+ * The contents of this file are subject to the terms of either the GNU
+ * General Public License Version 2 only ("GPL") or the Common
+ * Development and Distribution License("CDDL") (collectively, the
+ * "License"). You may not use this file except in compliance with the
+ * License. You can obtain a copy of the License at
+ * http://www.netbeans.org/cddl-gplv2.html
+ * or nbbuild/licenses/CDDL-GPL-2-CP. See the License for the
+ * specific language governing permissions and limitations under the
+ * License.  When distributing the software, include this License Header
+ * Notice in each file and include the License file at
+ * nbbuild/licenses/CDDL-GPL-2-CP.  Sun designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Sun in the GPL Version 2 section of the License file that
+ * accompanied this code. If applicable, add the following below the
+ * License Header, with the fields enclosed by brackets [] replaced by
+ * your own identifying information:
+ * "Portions Copyrighted [year] [name of copyright owner]"
+ *
+ * Contributor(s):
+ *
+ * The Original Software is NetBeans. The Initial Developer of the Original
+ * Software is Sun Microsystems, Inc. Portions Copyright 1997-2006 Sun
+ * Microsystems, Inc. All Rights Reserved.
+ *
+ * If you wish your version of this file to be governed by only the CDDL
+ * or only the GPL Version 2, indicate your decision by adding
+ * "[Contributor] elects to include this software in this distribution
+ * under the [CDDL or GPL Version 2] license." If you do not indicate a
+ * single choice of license, a recipient has the option to distribute
+ * your version of this file under either the CDDL, the GPL Version 2 or
+ * to extend the choice of license to its licensees as provided above.
+ * However, if you add GPL Version 2 code and therefore, elected the GPL
+ * Version 2 license, then the option applies only if the new code is
+ * made subject to such option by the copyright holder.
+ */
+
+package org.openide.filesystems;
+
+import java.io.IOException;
+import java.net.URL;
+import org.netbeans.junit.*;
+
+
+public class MutilFileSystemLayeredDeliveryTest extends NbTestCase {
+    MultiFileSystem down;
+    MultiFileSystem top;
+    LocalFileSystem lfs;
+
+    public MutilFileSystemLayeredDeliveryTest(String test) {
+        super(test);
+    }
+
+    @Override
+    protected void setUp() throws Exception {
+        down = new MultiFileSystem();
+        FileSystem mfs = new MultiFileSystem(new FileSystem[] { down });
+        for (int i = 0; i < 5; i++) {
+            mfs = new MultiFileSystem(new FileSystem[] {
+                mfs
+            });
+        }
+        lfs = new LocalFileSystem();
+        lfs.setRootDirectory(getWorkDir());
+        top = new MultiFileSystem (new FileSystem[] {lfs,mfs});
+    }
+
+    public void testHowManyChanges() throws Exception {
+        L l = new L();
+
+        FileObject fo = FileUtil.createFolder(top.getRoot(), "testMethodValue");
+        FileObject mv = FileUtil.createFolder(top.getRoot(), "testMV");
+        fo.addFileChangeListener(l);
+        mv.addFileChangeListener(l);
+        assertEquals("No children yet", 0, fo.getChildren().length);
+        assertNull("No value for ", fo.getAttribute("value1"));
+        assertEquals("No children yet", 0, mv.getChildren().length);
+        assertNull("No value for ", mv.getAttribute("value1"));
+
+
+        final FileSystem fs = FileUtil.createMemoryFileSystem();
+        down.setDelegates(fs);
+        FileUtil.runAtomicAction(new Runnable() {
+            public void run() {
+                try {
+                    final FileObject tmv = fs.getRoot().createFolder("testMethodValue");
+                    final FileObject tmv2 = fs.getRoot().createFolder("testMV");
+                    for (int i = 0; i < 10; i++) {
+                        tmv.setAttribute("value" + i, i);
+                        tmv2.setAttribute("value" + i, i);
+                    }
+                } catch (IOException ex) {
+                    fail(ex.getMessage());
+                }
+            }
+        });
+
+        assertNotNull("Some value for ", fo.getAttribute("value1"));
+
+        assertEquals("Ten changes", 20, l.change);
+        assertEquals("One Run", 1, l.run);
+
+        l.change = 0;
+        l.run = 0;
+
+        final FileSystem fs2 = FileUtil.createMemoryFileSystem();
+        final FileObject tmv = fs2.getRoot().createFolder("testMethodValue");
+        final FileObject tmv2 = fs2.getRoot().createFolder("testMV");
+        down.setDelegates(fs2);
+
+        assertEquals("No attributes", false, fo.getAttributes().hasMoreElements());
+        assertEquals("No attributes", false, mv.getAttributes().hasMoreElements());
+
+        assertEquals("Two changes", 2, l.change);
+        assertEquals("One Run", 1, l.run);
+    }
+
+    private static class L implements FileChangeListener, Runnable {
+        int change;
+        int run;
+
+        private void event(FileEvent ev) {
+            change++;
+            int prev = run;
+            ev.runWhenDeliveryOver(this);
+            assertEquals("Delivery is not immediate", prev, run);
+        }
+
+        public void run() {
+            run++;
+        }
+
+
+        public void fileFolderCreated(FileEvent fe) {
+            event(fe);
+        }
+
+        public void fileDataCreated(FileEvent fe) {
+            event(fe);
+        }
+
+        public void fileChanged(FileEvent fe) {
+            event(fe);
+        }
+
+        public void fileDeleted(FileEvent fe) {
+            event(fe);
+        }
+
+        public void fileRenamed(FileRenameEvent fe) {
+            event(fe);
+        }
+
+        public void fileAttributeChanged(FileAttributeEvent fe) {
+            event(fe);
+        }
+    } // end of L
+}