Lectura y escritura de ficheros en Java

Podemos hacer la lectura y escritura de ficheros con FileInputStream, que va carácter a carácter.

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 podemos utilizar las lecturas con 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();         }     } } }