java - Write message from IRC channel into a file with PircBotX -

hello pretty new java have fiddled bit.

this time trying make bot twitch channel can configure on own, making raffle , other independent stuff.

i using library connect twitch irc called pircbotx: https://code.google.com/p/pircbotx/ , have understanding on how answer listeneradapter so:

public class commands extends listeneradapter {     public void onmessage(messageevent event) {         if (event.getmessage().equals("!commands")) {             event.respond("available user commands: !topic, !faq, !youtube, !twitter, !schedule, !time");         }     } } 

but in particular listener trying return message when person does:

!topic newtopic 

in instance need "newtopic" string.

i don't know if there way save topic in twitch api write in own file.

i thinking might this:

newtext = event.getmessage.?????  if (event.getmessage().equals("!topic " + newtext)) {      if (event.getchannel().isop(event.getuser())) {          try (bufferedwriter br = new bufferedwriter(new filewriter("topic.txt"))) {             br.write(newtext);             br.close();             event.getchannel().send().message("topic: " + newtext);         }     }      else {         event.respond("only mods can change topic");     } } 

am doing wrong?

i have looked through api , don't understand how works. can help?

i might want answer own question people might similar dilemma.

this how declare string, easy:

string newtext = event.getmessage().substring(("!topic ").length()); 

i remember using substring() many times. little stupid mistake.

for more info on check here:

http://www.tutorialspoint.com/java/java_string_substring.htm