/*.................................................................................................................*/
 public Object doCommand(String commandName, String arguments, CommandChecker checker) {
   if (checker.compare(
       this.getClass(), "Sets the username", "[username]", commandName, "setUsername")) {
     username = parser.getFirstToken(arguments);
   }
   return null;
 }
 /*.................................................................................................................*/
 public Object doCommand(String commandName, String arguments, CommandChecker checker) {
   if (checker.compare(
       this.getClass(),
       "Sets the running file path",
       "[file path]",
       commandName,
       "setRunningFilePath")) {
     runningFilePath = parser.getFirstToken(arguments);
   } else if (checker.compare(
       this.getClass(),
       "Sets the output file paths",
       "[file paths]",
       commandName,
       "setOutputFilePaths")) {
     int num = parser.getNumberOfTokens(arguments);
     outputFilePaths = new String[num];
     if (num > 0) outputFilePaths[0] = parser.getFirstToken();
     for (int i = 1; i < num; i++) outputFilePaths[i] = parser.getNextToken();
   }
   return null;
 }