[Java] Java heap: Shallow and retained sizes

最近在試MAT工具找客戶的問題，快速筆記一下:D


參考：
Memory Analyzer tool(MAT)分析内存泄漏---理解Retained Heap、Shallow Heap、GC Root
<实战> 通过分析Heap Dump 来了解 Memory Leak ,Retained Heap,Shallow Heap
Shallow and retained sizes