java，String.split用法

1 当分隔符出现在字符串开头，则开头处有n个分隔符则生成n个空字符串""【开头,n->n】

2 当分隔符出现在字符串中间，比如中间某子串（连续分隔符）长度是n，则会生成n-1个空字符串""【中间,n->n-1】

3 当分隔符出现在字符串末尾，则会忽略掉，不会生成任何字符串【末尾,n->0】

基于jdk1.8

        String s14 = "1::";
        String[] arr14 = s14.split(":");//{"1"}

        String s13 = "::1";
        String[] arr13 = s13.split(":");//{"","","1"}

        String s12 = "cs::ab::";
        String[] arr12 = s12.split(":");//{"cs","","ab"}

        String s11 = "cs::ab";
        String[] arr11 = s11.split(":");//{"cs","","ab"}