JVM的内存区域划分(jdk7和jdk8)

参考：

https://blog.csdn.net/l1394049664/article/details/81486470?tdsourcetag=s_pctim_aiomsg

https://blog.csdn.net/Sugar_Rainbow/article/details/68150249

https://blog.csdn.net/zm13007310400/article/details/77534349