java string split 怎么保留尾部空字符串

# 不保留尾部空字符串

public class QQ {

    public static void main(String[] args) {

        String str = "a,b,c,d,";

        String[] strArr = str.split(",");

        System.out.println(JSON.toJSON(strArr));

    }

}

# 保留尾部空字符串

public class QQ {

    public static void main(String[] args) {

        String str = "a,b,c,d,";

        String[] strArr = str.split(",", -1);

        System.out.println(JSON.toJSON(strArr));

    }

}