1 /*
   2  * Copyright (c) 2013, 2017, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.
   8  *
   9  * This code is distributed in the hope that it will be useful, but WITHOUT
  10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  12  * version 2 for more details (a copy is included in the LICENSE file that
  13  * accompanied this code).
  14  *
  15  * You should have received a copy of the GNU General Public License version
  16  * 2 along with this work; if not, write to the Free Software Foundation,
  17  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  18  *
  19  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  20  * or visit www.oracle.com if you need additional information or have any
  21  * questions.
  22  */
  23 
  24 /**
  25  * @test
  26  * @key headful
  27  * @bug 4980592 8171363
  28  * @summary   switching user in XP causes an NPE in
  29  *            sun.awt.windows.WWindowPeer.displayChanged
  30  * @requires (os.family == "windows")
  31  * @author son@sparc.spb.su: area=embedded
  32  * @run main DisplayChangedTest
  33  */
  34 
  35 import java.awt.Frame;
  36 import java.awt.Dialog;
  37 import java.awt.TextArea;
  38 import java.awt.peer.ComponentPeer;
  39 import java.awt.peer.FramePeer;
  40 import java.lang.reflect.Constructor;
  41 import java.lang.reflect.Method;
  42 import java.lang.reflect.Field;
  43 
  44 import sun.awt.AWTAccessor;
  45 
  46 public class DisplayChangedTest {
  47 
  48     /**
  49      * Test fails if it throws any exception.
  50      *
  51      * @throws Exception
  52      */
  53     private void init() throws Exception {
  54 
  55         if (!System.getProperty("os.name").startsWith("Windows")) {
  56             System.out.println("This is Windows only test.");
  57             return;
  58         }
  59 
  60         Frame frame = new Frame("AWT Frame");
  61         frame.pack();
  62 
  63         FramePeer frame_peer = (FramePeer) AWTAccessor.getComponentAccessor()
  64                 .getPeer(frame);
  65         Class comp_peer_class = Class.forName("sun.awt.windows.WComponentPeer");
  66         Field hwnd_field = comp_peer_class.getDeclaredField("hwnd");
  67         hwnd_field.setAccessible(true);
  68         long hwnd = hwnd_field.getLong(frame_peer);
  69 
  70         Class clazz = Class.forName("sun.awt.windows.WEmbeddedFrame");
  71         Constructor constructor = clazz
  72                 .getConstructor(new Class[]{long.class});
  73         Frame embedded_frame = (Frame) constructor
  74                 .newInstance(new Object[]{new Long(hwnd)});
  75         frame.setVisible(true);
  76 
  77         ComponentPeer peer = AWTAccessor.getComponentAccessor().getPeer(
  78                 embedded_frame);
  79         Class peerClass = peer.getClass();
  80         Method displayChangedM = peerClass.getMethod("displayChanged",
  81                 new Class[0]);
  82         displayChangedM.invoke(peer, null);
  83         embedded_frame.dispose();
  84         frame.dispose();
  85 
  86     }
  87 
  88     public static void main(String args[]) throws Exception {
  89         new DisplayChangedTest().init();
  90     }
  91 
  92 }