如何在循环的每次迭代中更改变量（Java）

Question

How can I have my variables change after every loop. I need the stated arraylist variables to go where the code is marked "HERE".

//variables i need to cycle through
static ArrayList<Integer> one1,two1,one2,two2=new ArrayList<>();

for(int i=0;i<4;i++){
  for(int j=0;j<word1[i].length();j++){
    if (word1[i].charAt(j)=='-'){
      HERE.add(j);
    } else if (word1[i].charAt(j)!='-') {
      HERE.add(null);
    }
  }
}

Is there a simple way i could do this without dozens of lines of code?

Answer 1

You can create your own here method that adds to multiple lists for you like this:

package com.sandbox;

import java.util.ArrayList;
import java.util.List;

public class Sandbox {


    public static void main(String[] args) {
        List<Integer> l1 = new ArrayList<Integer>();
        List<Integer> l2 = new ArrayList<Integer>();
        List<Integer> l3 = new ArrayList<Integer>();
        here(1, l1, l2, l3);
    }

    public static void here(Integer integer, List<Integer>... lists) {
        for (List<Integer> list : lists) {
            list.add(integer);
        }
    }

}

The ... is called a varargs and you can learn more about it here. Just call this every time you have HERE.add in your current code like this: here(j, one1, two1, one2, two2)

But I think you're probably doing something wrong here. Why do you want to do this?

Answer 2

将您的列表放入数组。

for(List<Integer> HERE: new List<Integer>[]{ one1,two1,one2,two2})