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class Exec extends Thread  {
  InputStream is;
  String type;
  OutputStream os;

  Exec(InputStream is, String type) {
    this(is, type, null);
  }

  Exec(InputStream is, String type, OutputStream redirect) {
    this.is = is;
    this.type = type;
    this.os = redirect;
  }

  public void run() {
    try {
      PrintWriter pw = null;
      if (os != null) {
        pw = new PrintWriter(os);
      }  
     
      InputStreamReader isr = new InputStreamReader(is);
      BufferedReader br = new BufferedReader(isr);
      String line=null;
 
      while ( (line = br.readLine()) != null) {
        if (pw != null) {
          pw.println(line);
          pw.flush();
        }
 
        System.out.println(type + ">" + line);
      }
 
      if (pw != null)
        pw.flush();
    } catch (IOException ioe) { /* Forward to handler */ }
  }
}
	
public class ExecMe {
  public static void main(String[] args) {
    // ... perform command argument check  ...
	
    try {
      FileOutputStream fos = new FileOutputStream("c:\\output.txt");
      Runtime rt = Runtime.getRuntime();
      Process proc = rt.exec("notemaker");

      // any error message?
      Exec errorGobbler = new Exec(proc.getErrorStream(), "ERROR");
	
      // any output?
      Exec outputGobbler = new Exec(proc.getInputStream(), "OUTPUT", fos);
	
      errorGobbler.start();
      outputGobbler.start();
	
      // any error?
      int exitVal = proc.waitFor();
      errorGobbler.join();     // handle condition where the
      outputGobbler.join();    // process ends before the threads finish 

      fos.flush();
      fos.close();
    } catch (Throwable t) { /* forward to handler */ }
  }
}