这里回答了很多经典的Java系统级别的问题:
http://www.javaolympus.com/J2SE/JavaPerformance/JavaReflectionPerformance.jsp
To see a world in a grain of sand.
And a heaven in a wild flower
Hold infinity in the palm of your hand.
And eternity in an hour
一花一世界
一沙一天堂
掌中握无限
霎那成永恒
