Podem fer la lectura i escriptura de fitxers amb FileInputStream, que va caràcter a caràcter.
public class Stream {
public static void main(String[] args) throws IOException {
FileInputStream in = null;
FileOutputStream out = null;
try {
in = new FileInputStream("entrada.txt");
out = new FileOutputStream("sortida.txt");
int c;
while ((c = in.read()) != -1) {
System.out.println(c);
out.write(c);
}
} finally {
if (in != null) {
in.close();
}
if (out != null) {
out.close();
}
}
}
}
o podem utilitzar les lectures amb buffered.
public class ReaderWriter {
public static void main(String[] args) throws IOException {
BufferedReader inputStream = null;
PrintWriter outputStream = null;
try {
inputStream = new BufferedReader(new FileReader("entrada.txt"));
outputStream = new PrintWriter(new FileWriter("sortida.txt"));
String l;
while ((l = inputStream.readLine()) != null) {
System.out.println(l);
outputStream.println(l);
}
} finally {
if (inputStream != null) {
inputStream.close();
}
if (outputStream != null) {
outputStream.close();
}
}
}
}