public void setTopic(String newTopic){
        // create lock file and echo the old file into that until it finds topic
        // then change that line and echo it back to the old file
        // finally delete lock file
        FileIO file = new FileIO("IRChat" + ServerThread.seperator + "conf", channelName + ".conf", false);
        file.writeLn("NAME: " + channelName);
        file.writeLn("TOPIC: " + newTopic);
        
        String admins = "";
        for (int i=0;i<admin.size();i++){
            admins += admin.get(i) + ",";
        }        
        file.writeLn("ADMINS: " + admins);
        file.close();
        
        topic = findTopic();
    }