Валидатор ругается, программа работает правильно
package com.javarush.task.task19.task1925;
/*
Длинные слова
*/
import java.io.*;
import java.util.ArrayList;
public class Solution {
public static void main(String[] args) throws IOException {
BufferedReader reader = new BufferedReader(new FileReader(args[0]));
BufferedWriter writer = new BufferedWriter(new FileWriter(args[1]));
String [] words = new String[0];
ArrayList <String> list = new ArrayList<>();
while (reader.ready()){
list.add(reader.readLine());
}
boolean first = true;
for (String str : list){
words = str.split(" ");
for (String word : words){
if (first){
writer.write(word);
first = false;
} else if(word.length()>6 )
writer.write("," + word);
}
}
reader.close();
writer.close();
}
}