Java I/O学习 标准的I/O重定向

public class Test{

  /*
   * 标准的I/O重定向
   * System.setIn(InputStream)
   * System.setOut(PrintStream)
   * System.setErr(PrintStream)
   */
  public static void main(String[] args) throws IOException {
    PrintStream console = System.out;
    BufferedInputStream in = new BufferedInputStream(new FileInputStream("/home/estar/Test/a.java"));
    PrintStream out = new PrintStream("and.out");

    System.setIn(in);
    System.setOut(out);
    System.setErr(out);

    BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    String s = null;
    while ((s = br.readLine()) != null) {
      System.out.println(s);
    }
    out.close();
    System.setOut(console);

  }
}