--- old/src/java.desktop/share/classes/java/awt/MouseInfo.java	2015-03-11 15:21:13.264346500 +0300
+++ new/src/java.desktop/share/classes/java/awt/MouseInfo.java	2015-03-11 15:21:12.694294900 +0300
@@ -113,9 +113,12 @@
     /**
      * Returns the number of buttons on the mouse.
      * On systems without a mouse, returns <code>-1</code>.
+     * The number of buttons is obtained by calling
+     * Toolkit.getDesktopProperty("awt.mouse.numButtons").
      *
      * @exception HeadlessException if GraphicsEnvironment.isHeadless() returns true
      * @return number of buttons on the mouse
+     * @see Toolkit#getDesktopProperty
      * @since 1.5
      */
     public static int getNumberOfButtons() throws HeadlessException {