“”.length()与“”.split(",").length

public class test {
    public static void main(String[] args){
        String str = "";
        System.out.println(str.length());
        System.out.println(str.split(",").length);
        System.out.println(str.split(",")[0]);
        System.out.println(“Over！”);
       }
        
}

输出为：

0

1

Over！