RandomAccess接口里,JDK自带的说明有点奇怪

无意中在RandomAccess接口里,看到JDK自带的说明有如下一段

It is recognized that the distinction between random and sequential access is often fuzzy. For example, some List implementations provide asymptotically linear access times if they get huge, but constant access times in practice.Such a List implementation should generally implement this interface. As a rule of thumb, a List implementation should implement this interface if, for typical instances of the class, this loop:

     for (int i=0, n=list.size(); i < n; i++)
         list.get(i);

runs faster than this loop:
     for (Iterator i=list.iterator(); i.hasNext(); )
         i.next();

这段话的意思,难道遍历List for 循环遍历 要比 get 更比Iterator 更快?

凭直觉应该是 Iterator 更快吧。

说到随机访问的话,HashMap 应该更多地进行随机访问吧,可JDK 里偏偏 HashMap 没有实现 RandomAcess接口

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