virtualModem/src/net/hoo2/auth/vmodem/Echo.java

package net.hoo2.auth.vmodem;

import java.io.IOException;
import java.io.PrintWriter;

class Echo {
   static final int ECHO_DURATION_DEFAULT = 60;
   static final int ECHO_CODE_SIZE        = 5;
   static final int ECHO_BUFFER_SIZE      = 256;
   static final int ECHO_RESPONSE_SIZE    = 35;
   static final String ECHO_DELIMITER     = "PSTOP";

   private Com         com_;
   private Transaction transaction_;
   private int         duration_;
   private String      logfile_;
   
   Echo (Com com, byte[] code, int duration, String logfile) {
      com_        = com;
      duration_   = duration;
      transaction_= new Transaction(new byte[ECHO_CODE_SIZE],
                                    new byte[ECHO_BUFFER_SIZE]);
      transaction_.code = code.clone();
      logfile_    = logfile;
   }
   
   void run (boolean verbose) {
      boolean init;
      long start;
      long now;
      PrintWriter writer = null;
      String line;

      line = "Running echo with: " + new String(transaction_.code);
      System.out.println(line);
      if (logfile_ != null) {
         try {
            writer = new PrintWriter(logfile_);
            writer.println(line);
         }
         catch (IOException exp) {
            System.err.println( "Open log file failed: " + exp.getMessage() );
            return;
         }
      }
      init = true;
      start = System.currentTimeMillis();
      do {
         if (init == true) {
            transaction_ = com_.request (transaction_, false, null);
            init = false;
            line = new String(transaction_.response);
            if (verbose) {
               System.out.println(line);
            }
         }
         else {
            transaction_ = com_.request(transaction_, true, ECHO_DELIMITER.getBytes());
            line = new String(transaction_.code)
                 + ": "
                 + new String(transaction_.response).substring(0, 35)
                 + "  Resp.time= "
                 + (transaction_.arrival - transaction_.departure)
                 + " [msec]";
            if (logfile_ != null) writer.println(line);
            if (verbose)          System.out.println(line);

         }
         now = System.currentTimeMillis();
      } while (now - start < duration_*1000);
      
      try {
         if (writer != null)
            writer.close();
      } catch (Exception ex) {/*ignore*/}
   }
   
}