@Override
public boolean onCommand(String label, String[] args, MessageChannel channel, User author, Message message) {

    new Thread() {
        @SuppressWarnings("static-access")
        @Override
        public void run() {
            MessageHistory history = channel.getHistory();
            while (history.retrievePast(100).complete().size() != 0);
            history.retrievePast(100).complete();
            List<Message> messages = history.getRetrievedHistory();
            String fileName = channel.getName() + "-" + channel.getId() + ".txt";

            File file = new File("logs", fileName);
            file.getParentFile().mkdirs();
            if (!file.exists())
                try {
                    file.createNewFile();
                } catch (IOException e) {
                    e.printStackTrace();
                }

            BufferedWriter writer = null;
            try {
                writer = new BufferedWriter(new OutputStreamWriter(new FileOutputStream(file, true), Charset.forName("UTF-8")));
                writer.write("");
            } catch (IOException e1) {
                e1.printStackTrace();
            }
            for (int i = messages.size() - 1; i >= 0; i--) {
                Message msg = messages.get(i);
                OffsetDateTime time = msg.getCreationTime();
                try {
                    String line = "[" + time.format(DateTimeFormatter.ofPattern("MM/dd/YYYY - hh:mma")) + "] " + msg.getAuthor().getName() + "#" + msg.getAuthor().getDiscriminator() + ": " + msg.getContentRaw();
                    writer.append(line);
                    writer.newLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            try {
                writer.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }.start();