十六、curator recipes之DistributedIdQueue
简介
curator实现了一种分布式ID队列,也是遵循FIFO原则,比普通队列新增的一个点是ID队列可以根据ID对队列元素进行操作,比如移除该元素。
官方文档:http://curator.apache.org/curator-recipes/distributed-id-queue.html
javaDoc:http://curator.apache.org/apidocs/org/apache/curator/framework/recipes/queue/DistributedIdQueue.html
代码示例
import org.apache.curator.framework.CuratorFramework; import org.apache.curator.framework.CuratorFrameworkFactory; import org.apache.curator.framework.recipes.queue.*; import org.apache.curator.framework.state.ConnectionState; import org.apache.curator.retry.ExponentialBackoffRetry; import java.io.UnsupportedEncodingException; public class DistributedIdQueueDemo { private static CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181", new ExponentialBackoffRetry(3000, 2)); private static String path = "/queue/0002"; private static DistributedIdQueue<String> queue; static { client.start(); } public static void main(String[] args) throws Exception { QueueConsumer<String> consumer = new QueueConsumer<String>() { @Override public void stateChanged(CuratorFramework curatorFramework, ConnectionState connectionState) { System.out.println("state changed"); } @Override public void consumeMessage(String s) { System.out.println("消费数据:" + s); } }; queue = QueueBuilder.builder(client, consumer, new QueueSerializer<String>() { @Override public byte[] serialize(String s) { try { return s.getBytes("utf-8"); } catch (UnsupportedEncodingException e) { e.printStackTrace(); } return null; } @Override public String deserialize(byte[] bytes) { return new String(bytes); } }, path).buildIdQueue(); queue.start(); System.out.println("queue built"); queue.put("a", "1"); queue.put("b", "2"); System.out.println("put ended"); Thread.sleep(1000); queue.remove("1"); queue.remove("2"); System.out.println("remove ended"); Thread.sleep(100); queue.close(); Thread.sleep(50000); client.close(); } }