如何遍历数组列表并使用for循环每X次执行一次操作？ Java

Question

我想通过由解析HTML行组成的字符串的ArrayList迭代。如何使用double for循环打印0-353，同时每4个打印一行？感谢所有帮助

我必须做的是去每一行，检查它是否是世界，国家，成员或活动。我会将所有4个数据添加到一个对象中，每次完成填充对象时，我都必须开始一个新对象以添加到另一个对象的数组列表中。

<a id='slu-world-301' class='server-list__world-link'  href='http://oldschool.runescape.com/game?world=301'>Old School 1</a> 
<td class='server-list__row-cell server-list__row-cell--country server-list__row-cell--US'>United States</td> 
<td class='server-list__row-cell server-list__row-cell--type'>Free</td> 
<td class='server-list__row-cell'>Trade - Free</td> 
<a id='slu-world-302' class='server-list__world-link' href='http://oldschool.runescape.com/game?world=302'>Old School 2</a> 
<td class='server-list__row-cell server-list__row-cell--country server-list__row-cell--GB'>United Kingdom</td> 
<td class='server-list__row-cell server-list__row-cell--type'>Members</td> 
<td class='server-list__row-cell'>Trade - Members</td> 
<a id='slu-world-303' class='server-list__world-link' href='http://oldschool.runescape.com/game?world=303'>Old School 3</a> 
<td class='server-list__row-cell server-list__row-cell--country server-list__row-cell--DE'>Germany</td> 
<td class='server-list__row-cell server-list__row-cell--type'>Members</td> 
<td class='server-list__row-cell'>-</td> 

我当前的代码：

for(int i=1;i<(strs.size()/4) + 1;i++){ 
    for(int j=0;j<4;j++){ 
     System.out.println(???? WHAT DO I PUT HERE ????) 
    } 
     System.out.println("-----------------"); 
} 

Answer 1

我建议使用此％余运营商
参考https://docs.oracle.com/javase/tutorial/java/nutsandbolts/op1.html

0 % 4 = 0 
1 % 4 = 1 
2 % 4 = 2 
3 % 4 = 3 
4 % 4 = 0 



for(int i = 0; i < strs.size(); i++){ 
    System.out.println(i); 
    if (i%4 == 3) { 
     System.out.println("---------"); 
    } 
} 

输出

0 
1 
2 
3 
--------- 
4 
5 
6 
7 
--------- 
8 
9 
10 
11 
--------- 

---

如果代码如下

for(int i=0;i<strs.size();i++) { 
    if(i%4 ==0) { 
     System.out.println("---------"); 
    } 
    System.out.println(i); 
} 

输出将是

------------ //will more one ----- because 0 % 4 = 0 
0 
1 
2 
3 
------------ 
4 
5 
6 
7 
------------ 
8 
9 

---

Answer 2

它打印我们唯一的0-351是

i<(strs.size()/4) 

因为strs.size() = 354或353（从评论），您的外环变得

原因

for(int i=0;i< 88;i++) 

，因此您可以达到最大值87*4 + 3 =>351。

---

您可以更改为迭代：

for(int i=0;i<strs.size();i++) { 
    if(i%4 ==0) { 
     System.out.println("---------"); 
    } 
    System.out.println(i); 
}