發布訂閱 · JAVA

[TOC] # 消息監聽器類 ~~~ import redis.clients.jedis.JedisPubSub; public class RedisMsgPubSubListener extends JedisPubSub { @Override public void unsubscribe() { super.unsubscribe(); } @Override public void unsubscribe(String... channels) { super.unsubscribe(channels); } @Override public void subscribe(String... channels) { super.subscribe(channels); } @Override public void psubscribe(String... patterns) { super.psubscribe(patterns); } @Override public void punsubscribe() { super.punsubscribe(); } @Override public void punsubscribe(String... patterns) { super.punsubscribe(patterns); } @Override public void onMessage(String channel, String message) { System.out.println("---onMessage---"); System.out.println("channel:" + channel + "receives message :" + message); System.out.println("---onMessage---"); //取消訂閱的話就這樣,但是后續也就不再監聽了 // this.unsubscribe(); } @Override public void onPMessage(String pattern, String channel, String message) { } @Override public void onSubscribe(String channel, int subscribedChannels) { System.out.println("---onSubscribe---"); System.out.println("channel:" + channel + "is been subscribed:" + subscribedChannels); System.out.println("---onSubscribe---"); } @Override public void onPUnsubscribe(String pattern, int subscribedChannels) { } @Override public void onPSubscribe(String pattern, int subscribedChannels) { } @Override public void onUnsubscribe(String channel, int subscribedChannels) { System.out.println("---onUnsubscribe---"); System.out.println("channel:" + channel + "is been unsubscribed:" + subscribedChannels); System.out.println("---onUnsubscribe---"); } } ~~~ 該類需要繼承JedisPubSub ，并實現其抽象方法，通過方法的名稱很清楚的看出來，這個監聽器是用來訂閱一個頻道，在訂閱該頻道，可以選擇取消訂閱，收到消息后也可以再調用其他方法 # 訂閱測試類 ~~~ @Test public void testSubscribe() throws Exception { //創建一個jedis客戶端對象(redis的客戶端連接) Jedis jedis = new Jedis("127.0.0.1", 6379); //設置auth密碼 jedis.auth("root"); RedisMsgPubSubListener listener = new RedisMsgPubSubListener(); jedis.subscribe(listener, "redisChatTest"); //other code } ~~~ 該類實現對頻道redisChatTest的訂閱監聽，頻道的訂閱，取消訂閱，收到消息都會調用listener對象的對應方法注意：subscribe是一個阻塞的方法，在取消訂閱該頻道前，會一直阻塞在這. 只有當取消了訂閱才會執行下面的other code，參考上面代碼，我在onMessage里面收到消息后，如果調用了this.unsubscribe(); 來取消訂閱，這樣才會執行后面的other code # 發布消息測試類 ~~~ @Test public void testPublish() throws Exception { //創建一個jedis客戶端對象(redis的客戶端連接) Jedis jedis = new Jedis("127.0.0.1", 6379); //設置auth密碼 jedis.auth("root"); jedis.publish("redisChatTest", "我是天才"); Thread.sleep(5000); jedis.publish("redisChatTest", "我牛逼"); Thread.sleep(5000); jedis.publish("redisChatTest", "哈哈"); } ~~~ 這個類向頻道redisChatTest發布消息，第二步因為訂閱了該頻道，所以會收到該消息。