http://rednaxelafx.iteye.com/blog/1549577
https://www.jianshu.com/p/f98c3acd8df8
http://download.java.net/openjdk/jdk6/
http://java-mzd.iteye.com/blog/838514
http://www.cnblogs.com/qiuting/p/5308877.html
