給定分割長度，分割給定字元串

public class aasa {
        public static void main(String[] args) {
            String a[] = split("aaabbbcccdddffff", 3);
            for (int i = 0; i < a.length; i++) {
                System.out.println(a[i]);
            }
        }
    
        public static String[] split(String str ,int num){
    
            int a = 0;
    
            int num1 = str.length()%num==0?str.length()/num:str.length()/num+1;
    
            String s[] = new String[num1];
    
            for (int i = 0; i <str.length() ; i += num) {
    
                if(num+i<str.length()){
                    s[a] = str.substring(i,num+i);
                }else {
                    s[a] = str.substring(i);
                }
                a++;
                System.out.println(a);
    
            }
    
        return s;
    
        }
    }