| package org.apache.log4j.net; |
| |
| import javax.jmdns.JmDNS; |
| |
| /** |
| * This singleton holds the single instance of the JmDNS instance that is used to broadcast |
| * Appender related information via ZeroConf. Once referenced, a single JmDNS instance is created |
| * and held. To ensure your JVM exits cleanly you should ensure that you call the {@link #shutdown() } method |
| * to broadcast the disappearance of your devices, and cleanup sockets. (alternatively you can call the close() |
| * method on the JmDNS instead, totally up to you...) |
| * |
| * See http://jmdns.sf.net for more information about JmDNS and ZeroConf. |
| * |
| * @author psmith |
| * |
| */ |
| public class Zeroconf4log4j { |
| |
| private static final JmDNS instance; |
| |
| static { |
| try { |
| instance = new JmDNS(); |
| } catch (Exception e) { |
| e.printStackTrace(); |
| throw new RuntimeException("Failed to initialize JmDNS"); |
| } |
| } |
| |
| /** |
| * Returns the current instance of the JmDNS being used by log4j. |
| * |
| * @throws IllegalStateException if JmDNS was not correctly initialized. |
| * |
| * @return |
| */ |
| public static JmDNS getInstance() { |
| checkState(); |
| return instance; |
| } |
| |
| private static void checkState() { |
| if (instance == null) { |
| throw new IllegalStateException( |
| "JmDNS did not initialize correctly"); |
| } |
| } |
| |
| /** |
| * Ensures JmDNS cleanly broadcasts 'goodbye' and closes any sockets, and (more imporantly) |
| * ensures some Threads exit so your JVM can exit. |
| * |
| */ |
| public static void shutdown() { |
| checkState(); |
| instance.close(); |
| } |
| } |