Java集合类List⼀Set⼀Map的区别和联系

2024-12-31 13:45:37
推荐回答(2个)
回答1:

List 是一个父类 底下有 LinkedList 就是链表 一

ArrayList 我管这个叫集合数组
Set 是一个接口 底下各种实现类
Map 有两种 一种 在awt下 是一个类
通常我们都用的 是util包的 这里的map 是一个接口

这三个东西内容非常多
List 可重复
Set 不可重复
map 的key 通常不会重复
map的 value可重复
map 里面 储存的实际上是entry 实例
我记得老师说过有一种情况 好像entry 会相同的
对了 map的实际容量是 表面容量的3/4
可能是1/4的留给后面的散列算法吧 那样会合理给出key的

回答2:

List 是一个动态数组,里面的元素可重复
Map 是一个key/value形式的数据结构,key不可重复,value可相同
Set 是一个数组,但是里面的元素是不可重复的
接口的区别就这么多,具体的区别要看具体的实现类。

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