Add GetParent to User32

contrib/platform/src/com/sun/jna/platform/win32/User32.java

@@ -2274,6 +2274,30 @@ LRESULT SendMessageTimeout(HWND hWnd, int msg, WPARAM wParam, LPARAM lParam,
      */
     HWND GetAncestor(HWND hwnd, int gaFlags);
 
+    /**
+     * Retrieves a handle to the specified window's parent or owner.
+     *
+     * To retrieve a handle to a specified ancestor, use the GetAncestor function.
+     *
+     * @param hwnd
+     *            A handle to the window whose parent window handle is to be retrieved.
+     * @return Type: HWND<br />
+     *         If the window is a child window, the return value is a handle to the
+     *         parent window. If the window is a top-level window with the WS_POPUP style,
+     *         the return value is a handle to the owner window.
+     *
+     *         If the function fails, the return value is NULL. To get extended error
+     *         information, call GetLastError.
+     *
+     *         This function typically fails for one of the following reasons:
+     *         <ul>
+     *           <li>The window is a top-level window that is unowned or does not have
+     *           the WS_POPUP style
+     *           <li>The owner window has WS_POPUP style
+     *         </ul>
+     */
+    HWND GetParent(HWND hwnd);
+
     /**
      * Retrieves the position of the mouse cursor, in screen coordinates.
      *

contrib/platform/test/com/sun/jna/platform/win32/User32Test.java

@@ -377,6 +377,35 @@ public void testGetAncestor() {
         assertNull("GetAncestor result should be null", result);
     }
 
+    @Test
+    public void testGetParent() {
+        HWND desktopWindow = User32.INSTANCE.GetDesktopWindow();
+        assertNotNull("Failed to get desktop window HWND", desktopWindow);
+
+        HWND result = User32.INSTANCE.GetParent(desktopWindow);
+        assertNull("GetParent result should be null", result);
+
+        final JFrame parent = new JFrame("Parent");
+        JWindow child = new JWindow(parent);
+
+        try {
+            parent.setVisible(true);
+            child.setVisible(true);
+
+            HWND parentHwnd = new HWND();
+            parentHwnd.setPointer(Native.getComponentPointer(parent));
+
+            HWND childHwnd = new HWND();
+            childHwnd.setPointer(Native.getComponentPointer(child));
+
+            result = User32.INSTANCE.GetParent(childHwnd);
+            assertEquals("GetParent of child should be parent", parentHwnd, result);
+        } finally {
+            child.dispose();
+            parent.dispose();
+        }
+    }
+
     @Test
     public void testGetCursorPos() {
         POINT cursorPos = new POINT();