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http://www.99inf.net/SoftwareDev/Java/48702.htm

http://blog.sina.com.cn/s/blog_46e73e77010001cj.html

http://www.blogjava.net/flyingis/archive/2006/01/07/26973.html

http://www.594k.com/java/html/y2007m5/14355/