JFrame, JDialog and (as far as I know) all other window/frame classes in JFC are always opaque (cannot be transparent or semi-transparent). In other words, you cannot have a JFC window through which you can see other windows on your desktop or the desktop itself. Only the components added to these windows can be transparent/semi-transparent
不过用用Swt就可以做不规则窗体,包括透明窗体了
http://blog.csdn.net/chenweionline/archive/2007/08/27/1760779.aspx
包括透明度的实现也已经完成了,多谢各位关注!相关demo 在我的blog上面
http://blog.sina.com.cn/piratebase