Versions Compared

Old Version 2

changes.mady.by.user Kaifeng Xue

Saved on

compared with

New Version 3

changes.mady.by.user Kaifeng Xue

Saved on

Key

  • This line was added.
  • This line was removed.
  • Formatting was changed.

Table of Contents

背景

Java原生的HashMap受限于Java对象限制，对key和value都必须抽象封装为一个类，其实现为开地址法哈希+红黑树，hash槽中的节点为Node，需要存储左右孩子节点等信息，连同其引用一个Node占用内存为32字节。综上，每存储一个键值对就需要额外48字节的对象头及指针，内存空间开销大。

...