Подскажите, плз, в чем ошибка?
package com.javarush.task.task18.task1828;
import java.io.*;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.InputStreamReader;
import java.util.*;
import java.util.List;
/*
Прайсы 2
*/
public class Solution {
public static void main(String[] args) throws IOException{
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
String fileName = br.readLine();
br.close();
if (args.length == 0)
return;
String line;
FileReader fr = new FileReader(fileName);
BufferedReader br1=new BufferedReader(fr);
ArrayList<String> list = new ArrayList<>();
ArrayList<String> num = new ArrayList<>();
String id;
int index =0;
while((line = br1.readLine())!=null ){
id = line.substring(0,8).trim();
num.add(id);
list.add(line);
}
br1.close();
fr.close();
if (args[0].equals("-d") ){
for(String number:num )
if(args[1].substring(0,8).trim().equals(number))
index= num.indexOf(number);
list.remove(index);
}
else if(args[0].equals("-u") ){
for (String number:num){
if(args[1].equals(number))
index= num.indexOf(number);
}
String s= args[1]+args[2]+args[3]+args[4];
list.set(index,s.format("%-8s%-30s%-8s%-4s",args[1],args[2],args[3],args[4]));
FileWriter fw = new FileWriter(fileName);
fw.write(" ");
fw.flush();
for(String l:list){
fw.write(l+"\n");
}
fw.close();
}
}
}