Tentei fazer sozinho antes de assistir a proxima aula e funcionou certinho.
package br.com.fernando.java.io.teste;
import java.io.*;
public class TesteLeituraEscrita {
public static void main(String[] args) throws IOException {
// --> Entrada
InputStream file = new FileInputStream("pokemon.txt");
Reader ler = new InputStreamReader(file);
BufferedReader br = new BufferedReader(ler);
// -->Saida
OutputStream fos = new FileOutputStream("pokemon2.txt");
Writer oswr = new OutputStreamWriter(fos);
BufferedWriter bw = new BufferedWriter(oswr);
String linha = br.readLine();
// --> Reescrevendo o arquivo.
while(linha != null) {
bw.write(linha);
bw.newLine();
linha = br.readLine();
}
br.close();
bw.close();
}
}