Currently this reads:

    /**
     * The "mouse dragged" event. This <code>MouseMotionEvent</code>
     * occurs when the mouse position changes while the "drag"
     * No button has changed state
     */
    public static final int NOBUTTON = 0;

It should read:

    /**
     * No button has changed state
     */
    public static final int NOBUTTON = 0;

BTW, most of the constants have no @since tags. New methods such as
getButton() also need @since tags.