jvm内存回收机制

https://www.zhihu.com/question/35164211

http://www.importnew.com/16173.html

http://blog.csdn.net/justloveyou_/article/details/71189093

https://blog.csdn.net/justloveyou_/article/details/71189093

http://blog.csdn.net/justloveyou_/article/details/71216049

https://blog.csdn.net/justloveyou_/article/details/71216049