split(",")与split(",",-1)的区别

split(",")与split(",",-1)的区别

下面通过两种情况说明二者的区别

第一种：字符串最后一位是要切割符

代码：

package com.yyy.test;

public class testSplit {
    public static void main(String[] args) {
        String aaa="a,b,c,d,,,,,,";
        String[] split = aaa.split(",");
        System.out.println(split.length);
        for(String item:split){
            System.out.println(item+"==========");
        }
        System.out.println("1111111111111111111111111111111111111111111111111");
        String[] split1 = aaa.split(",", -1);
        System.out.println(split1.length);
        for (String item:split1){
            System.out.println(item+"==========");
        }
    }
}

执行结果

4
a==========
b==========
c==========
d==========
1111111111111111111111111111111111111111111111111
10
a==========
b==========
c==========
d==========
==========
==========
==========
==========
==========
==========

Process finished with exit code 0

总结：
第一种情况，二者的区别为，如果最后n位都为切割符则split(",")不会继续切割，而split(",",-1）会继续切割

---

---

第二种情况 字符串最后一位不为切割符

代码

package com.yyy.test;

public class testSplit2 {
    public static void main(String[] args) {
        String aaa="a,b,c,d,,,,,,e";
        String[] split = aaa.split(",");
        System.out.println(split.length);
        for(String item:split){
            System.out.println(item+"==========");
        }
        System.out.println("1111111111111111111111111111111111111111111111111");
        String[] split1 = aaa.split(",", -1);
        System.out.println(split1.length);
        for (String item:split1){
            System.out.println(item+"==========");
        }
    }
}

执行结果

10
a==========
b==========
c==========
d==========
==========
==========
==========
==========
==========
e==========
1111111111111111111111111111111111111111111111111
10
a==========
b==========
c==========
d==========
==========
==========
==========
==========
==========
e==========

Process finished with exit code 0

总结
第二种情况二者没有区别