使用的是com.sun.awt.AWTUtilities包
Jdk版本需要在 1.6U10及以上
参考文章:http://developers.sun.com.cn/Java/translucent-and-shaped-swing-windows.html
(http://souasou.blogbus.com/logs/33476389.html
http://souasou.blogbus.com/logs/33476456.html)
http://www.iteye.com/topic/229179
com.sun.awt.AWTUtilities.setWindowOpacity(w, 0.5f);
附件为官居方示例