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Java为什么建议初始化HashMap的容量大小?

在Java中，初始化HashMap的容量大小主要是为了提高性能。当我们创建一个新的HashMap时，它默认的初始容量是16，并且每次需要增长容量时，都会按照当前容量的1/2进行扩容。因此，如果我们可以预估HashMap的元素数量，那么初始化HashMap时设定一个合适的容量可以避免频繁的扩容操作。 ...

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更新时间 2024-02-23 16:23:45

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