* Ideally, under random hashCodes, the frequency of * nodes in bins follows a Poisson distribution * (http://en.wikipedia.org/wiki/Poisson_distribution) with a * parameter of about 0.5 on average for the default resizing * threshold of 0.75, although with a large variance because of * res...
同样在ArrayList中LinkedList中都是这种结构。 据java 集合框架的创始人Josh Bloch描述,这样的写法是一个失误。在java集合框架中,类似这样的写法很多,最开始写java集合框架的时候,他认为这样写,在某些地方可能是有价值的,直到他意识到错了。JDK的维护者,后来不认为这个小小的失误值得去修改,所以就这样存在下来了。 四...
HashMap负载因子为0.75是空间和时间成本的一种折中。 Ideally, under random hashCodes, the frequency of * nodes in bins follows a Poisson distribution * (http:///wiki/Poisson_distribution) with a * parameter of about 0.5 on average for the default resizing * threshold of 0.75, although with a ...
* (see TREEIFY_THRESHOLD). And when they become too small (due to * removal or resizing) they are converted back to plain bins. In * usages with well-distributed user hashCodes, tree bins are * rarely used. Ideally, under random hashCodes, the frequency of * nodes in bins follows a ...
Ideally, under random hashCodes, the frequency of nodes in bins follows a Poisson distribution (http://en.wikipedia.org/wiki/Poisson_distribution) with a parameter of about 0.5 on average for the default resizing threshold of 0.75, although with a large variance because of resizing granularity. ...
可以看出Node主要包含的属性有 hash值、key、value以及下一个节点的引用,而LinkedHashMap中的Entry继承了Node类,额外加了before和after节点的引用,TreeNode又继承之Entry类,又额外多了 parent、left、right、prev和red等字段。 1.3、HashMap的初始化 1/**默认无参构造函数*/2publicHashMap() {3//设置装载因子为...
据java 集合框架的创始人Josh Bloch描述,这样的写法是一个失误。在java集合框架中,类似这样的写法很多,最开始写java集合框架的时候,他认为这样写,在某些地方可能是有价值的,直到他意识到错了。显然的,JDK的维护者,后来不认为这个小小的失误值得去修改,所以就这样存在下来了。
rarely used. Ideally, under random hashCodes, the frequency of nodes in bins follows a Poisson distribution (http://en.wikipedia.org/wiki/Poisson_distribution) with a parameter of about 0.5 on average for the default resizing threshold of 0.75, although with a large variance because of ...
In usages with well-distributed user hashCodes, tree bins are rarely used. Ideally, under random hashCodes, the frequency of nodes in bins follows a Poisson distribution (http://en.wikipedia.org/wiki/Poisson_distribution) with a parameter of about 0.5 on average for the default resizing ...
(due to removal or resizing) they are converted back to plain bins. In usages withwell-distributed user hashCodes, tree bins are rarely used. Ideally, under random hashCodes,the frequency of nodes in bins follows a Poisson distribution(http://en.wikipedia.org/wiki/Poisson_distribution)with a...