else if (mainArg.equalsIgnoreCase("exchange"))
this.cmd = new ExchangeCmd(sender, args);
//Management commands
else if (mainArg.equalsIgnoreCase("add"))
this.cmd = new AddCmd(sender, args);
else if (mainArg.equalsIgnoreCase("get"))
this.cmd = new GetCmd(sender, args);
else if(mainArg.equalsIgnoreCase("owner"))
this.cmd = new OwnerCmd(sender, args);
else if (mainArg.equalsIgnoreCase("price"))