Java开发手册疑问-阿里云

JAVA开发手册(嵩山版)疑问 请问这里是笔误吗?

泰山版java开发手册的一个疑问【强制】判断所有集合内部的元素是否为空，使用 isEmpty()方法，而不是 size()==0 的方式。说明：前者的时间复杂度为 O(1)，而且可读性更好。正例： Map map = new HashMap<>(); if(map.isEmpty()) { System.out.p...

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