字符串分割问题
如逗号分割，如果逗号之间为空，那么分割长度不够，解决方式及示例如下：
String s2 = "a,b,,";
String[] x = s.split(",");
String[] x2 = s2.split(",");
String[] x3 = s2.split(",", -1);
System.out.println(x.length);
System.out.println(x2.length);
System.out.println(x3.length);
