please what is wrong with the code

package com.codegym.task.task09.task0921; import java.io.BufferedReader; import java.io.InputStreamReader; import java.util.ArrayList; import java.util.List; /* Method in a try-catch */ public class Solution { public static void main(String[] args) { readData(); } public static void readData() { //write your code here BufferedReader b = new BufferedReader(new InputStreamReader(System.in)); ArrayList<Integer> arr = new ArrayList<Integer>(); try{ arr.add(Integer.parseInt(b.readLine())); } catch(Exception e){ for (int i = 0; i < arr.size(); i++) System.out.println(arr.get(i)); } } }