zookeeper核心之使用 Zookeeper 实现 leader 选举

public class SelectorClient2 extends LeaderSelectorListenerAdapter implements Closeable {
		private final String name;
		private final LeaderSelector leaderSelector;

		public SelectorClient2(CuratorFramework client, String path, String name) {
			this.name = name;
			// 利用一个给定的路径创建一个 leader selector
			// 执行 leader 选举的所有参与者对应的路径必须一样
			// 本例中 SelectorClient 也是一个LeaderSelectorListener，但这不是必须的。
			leaderSelector = new LeaderSelector(client, path, this);
			// 在大多数情况下，我们会希望一个 selector放弃 leader 后还要重新参与 leader 选举
			leaderSelector.autoRequeue();
		}

		public void start() {
			leaderSelector.start();
		}

		@Override
		public void close() throws IOException {
			leaderSelector.close();
		}

		@Override
		public void takeLeadership(CuratorFramework curatorFramework) throws Exception {
			System.out.println(name + " 现在是 leader了，持续成为 leader ");
			// 选举为 master，
			System.in.read();// 阻塞，让当前获得 leader权限的节点一直持有，直到该进程关闭
		}

		private static String CONNECTION_STR = "192.168.13.102:2181,192.168.13.103:2181,192.168.13.104:2181";

		public static void main(String[] args) throws IOException {
			CuratorFramework curatorFramework = CuratorFrameworkFactory.builder().

			connectString(CONNECTION_STR).sessionTimeoutMs(5000).retryPolicy(new ExponentialBackoffRetry(1000, 3))
					.build();
			curatorFramework.start();
			SelectorClient2 sc = new SelectorClient2(curatorFramework, "/leader", "ClientB");
			sc.start();
			System.in.read();
		}
	}