где я не прав?
package com.javarush.task.task18.task1809;
import java.io.*;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
/*
Реверс файла
*/
public class Solution {
public static void main(String[] args) throws IOException{
BufferedReader reader =new BufferedReader (new InputStreamReader (System.in));
String file1 = reader.readLine();
String file2 = reader.readLine();
reader.close();
FileInputStream inputStream = new FileInputStream(file1);
FileOutputStream outputStream = new FileOutputStream (file2);
byte[] buffer = new byte[inputStream.available()];
if(inputStream.available() < 0){
inputStream.read(buffer);
}
inputStream.close();
for(int i = buffer.length-1; i>=0;i--){
outputStream.write(buffer[i]);
}
outputStream.close();
}
}