如上所述,我們將使用 Maven 來運行應用程序。這一次你需要打開兩個控制臺窗口給每個項目。用 Ctrl-C 可以停止它。 首先我們將啟動 LogEventBroadcaster 如清單13.4所示,除了已經構建項目以下命令即可(使用默認值): ~~~ $ mvn exec:exec -Pchapter13-LogEventBroadcaster ~~~ 和之前一樣,這將通過 UDP 廣播日志消息。 現在,在一個新窗口,構建和啟動 LogEventMonitor 接收和顯示廣播消息。 Listing 13.9 Compile and start the LogEventBroadcaster ~~~ $ mvn clean package exec:exec -Pchapter13-LogEventMonitor [INFO] Scanning for projects... [INFO] [INFO] -------------------------------------------------------------------- [INFO] Building netty-in-action 0.1-SNAPSHOT [INFO] -------------------------------------------------------------------- ... [INFO] [INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ netty-in-action --- [INFO] Building jar: /Users/norman/Documents/workspace-intellij/netty-in-actionprivate/ target/netty-in-action-0.1-SNAPSHOT.jar [INFO] [INFO] --- exec-maven-plugin:1.2.1:exec (default-cli) @ netty-in-action --- LogEventMonitor running ~~~ 當看到 “LogEventMonitor running” 說明程序運行成功了。 控制臺將顯示任何事件被添加到日志文件中,如下所示。消息的格式是由LogEventHandler 創建。 Listing 13.10 LogEventMonitor output ~~~ 1364217299382 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 13:55:08 dev-linux dhclient: DHCPREQUEST of 192.168.0.50 on eth2 to 192.168.0.254 port 67 1364217299382 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 13:55:08 dev-linux dhclient: DHCPACK of 192.168.0.50 from 192.168.0.254 1364217299382 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 13:55:08 dev-linux dhclient: bound to 192.168.0.50 -- renewal in 270 seconds. 1364217299382 [/192.168.0.38:63182] [[/var/log/messages] : Mar 25 13:59:38 dev-linux dhclient: DHCPREQUEST of 192.168.0.50 on eth2 to 192.168.0.254 port 67 1364217299382 [/192.168.0.38:63182] [/[/var/log/messages] : Mar 25 13:59:38 dev-linux dhclient: DHCPACK of 192.168.0.50 from 192.168.0.254 1364217299382 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 13:59:38 dev-linux dhclient: bound to 192.168.0.50 -- renewal in 259 seconds. 1364217299383 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 14:03:57 dev-linux dhclient: DHCPREQUEST of 192.168.0.50 on eth2 to 192.168.0.254 port 67 1364217299383 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 14:03:57 dev-linux dhclient: DHCPACK of 192.168.0.50 from 192.168.0.254 1364217299383 [/192.168.0.38:63182] [/var/log/messages] : Mar 25 14:03:57 dev-linux dhclient: bound to 192.168.0.50 -- renewal in 285 seconds. ~~~ 若你沒有訪問 UNIX syslog 的權限，可以創建 自定義的文件，手動填入內容。下面是 UNIX 命令用 touch 創建一個空文件 ~~~ $ touch ~/mylog.log ~~~ 再次啟動 LogEventBroadcaster，設置系統屬性 ~~~ $ mvn exec:exec -Pchapter13-LogEventBroadcaster -Dlogfile=~/mylog.log ~~~ 當 LogEventBroadcaster 運行時，你可以手動的添加消息到文件來查看廣播到 LogEventMonitor 控制臺的內容。使用 echo 和輸出的文件 ~~~ $ echo ’Test log entry’ >> ~/mylog.log ~~~ 你可以啟動任意個監視器實例，他們都會收到相同的消息。