java - 在java中将逗号附加到字符数组

Question

我有一个字符数组。我想在每个第三个字符后添加逗号(，)。我尝试了以下代码。

    public class Comma {
    char [] str = {'1','2','3','4','5','6','7','8','9'};
    char [] buf = new char[15];
    int size = str.length;
    int c=1;
    public void insert()
    {
            for(int i=0;i<size;i++)
            {
                  c++;
                  if(c%3==0)
                  {
                    buf[c] = ',';
                    i++;
                  }
                  buf[i]=str[i];
             }  
            System.out.println("Final String");
            for(int i=0;i<buf.length;i++)
            System.out.print(buf[i]);
   }
   public static void main(String args[])
   {
        Comma c = new Comma();
        c.insert();
   }

   }

我得到以下输出:

Final String
1 345 789

有人可以纠正我吗？

Answer 1

输出:

Final String
123,456,789

这是代码

public class Comma {
    char[] str = { '1', '2', '3', '4', '5', '6', '7', '8', '9' };
    char[] buf = new char[20];
    int size = str.length;
    int c = 1;<p></p>

<code>public void insert() {
    for (int i = 0; i < size; i++) {
        if (c % 4 == 0) {
            buf[c - 1] = ',';
            i--;
        } else {
            buf[c - 1] = str[i];
        }
        c++;
    }
    System.out.println("Final String");
    for (int i = 0; i < buf.length; i++) {
        System.out.print(buf[i]);
    }
}

public static void main(final String args[]) {
    Comma c = new Comma();
    c.insert();
}
</code>





}