--- a/jdk/src/share/classes/java/awt/Dialog.java	Thu Apr 07 22:34:29 2011 +0400
+++ b/jdk/src/share/classes/java/awt/Dialog.java	Fri Apr 08 15:00:20 2011 +0400
@@ -903,7 +903,7 @@
             if (peer == null) {
                 addNotify();
             }
-            validate();
+            validateUnconditionally();
             if (visible) {
                 toFront();
                 retval = false;

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/awt/Dialog/ValidateOnShow/ValidateOnShow.java	Fri Apr 08 15:00:20 2011 +0400
@@ -0,0 +1,84 @@
+/*
+ * 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.
+ *
+ * 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.
+ */
+
+/*
+  @test
+  @bug 7027013
+  @summary Dialog.show() should validate the window unconditionally
+  @author anthony.petrov@oracle.com: area=awt.toplevel
+  @run main ValidateOnShow
+*/
+
+import java.awt.*;
+
+public class ValidateOnShow {
+    private static Dialog dialog = new Dialog((Frame)null);
+    private static Panel panel = new Panel() {
+        @Override
+        public boolean isValidateRoot() {
+            return true;
+        }
+    };
+    private static Button button = new Button("Test");
+
+    private static void sleep() {
+        try { Thread.sleep(500); } catch (Exception e) {}
+    }
+
+    private static void test() {
+        System.out.println("Before showing: panel.isValid=" + panel.isValid() + "      dialog.isValid=" + dialog.isValid());
+        dialog.setVisible(true);
+        sleep();
+        System.out.println("After showing:  panel.isValid=" + panel.isValid() + "      dialog.isValid=" + dialog.isValid());
+
+        if (!panel.isValid()) {
+            dialog.dispose();
+            throw new RuntimeException("The panel hasn't been validated upon showing the dialog");
+        }
+
+        dialog.setVisible(false);
+        sleep();
+    }
+
+    public static void main(String[] args) {
+        // setup
+        dialog.add(panel);
+        panel.add(button);
+
+        dialog.setBounds(200, 200, 300, 200);
+
+        // The first test should always succeed since the dialog is invalid initially
+        test();
+
+        // now invalidate the button and the panel
+        button.setBounds(1, 1, 30, 30);
+        sleep();
+        // since the panel is a validate root, the dialog is still valid
+
+        // w/o a fix this would fail
+        test();
+
+        // cleanup
+        dialog.dispose();
+    }
+}