利用Zookeeper进行服务发现主要涉及以下几个步骤:
服务注册:
/services/{服务名称}/{服务实例的唯一标识}
。保持心跳:
服务发现:
具体实现:
import org.apache.zookeeper.*;
public class ServiceProvider {
private static final String ZOOKEEPER_ADDRESS = "localhost:2181";
private static final String SERVICE_PATH = "/services/my-service";
public static void main(String[] args) throws Exception {
ZooKeeper zooKeeper = new ZooKeeper(ZOOKEEPER_ADDRESS, 3000, event -> {
if (event.getState() == Event.KeeperState.SyncConnected) {
System.out.println("Connected to Zookeeper");
}
});
// 注册服务
String serviceInstance = SERVICE_PATH + "/instance1";
zooKeeper.create(serviceInstance, "127.0.0.1:8080".getBytes(), ZooDefs.Ids.OPEN_ACL_UNSAFE, CreateMode.EPHEMERAL);
// 保持服务存活状态
while (true) {
Thread.sleep(1000);
}
}
}
public class ServiceConsumer {
private static final String ZOOKEEPER_ADDRESS = "localhost:2181";
private static final String SERVICE_PATH = "/services/my-service";
public static void main(String[] args) throws Exception {
ZooKeeper zooKeeper = new ZooKeeper(ZOOKEEPER_ADDRESS, 3000, null);
// 监听节点变化
List<String> serviceInstances = zooKeeper.getChildren(SERVICE_PATH, new Watcher() {
@Override
public void process(WatchedEvent event) {
if (event.getType() == Event.EventType.NodeChildrenChanged) {
try {
List<String> updatedInstances = zooKeeper.getChildren(SERVICE_PATH, this);
System.out.println("Updated service instances: " + updatedInstances);
} catch (Exception e) {
e.printStackTrace();
}
}
}
});
// 输出初始的服务实例
System.out.println("Initial service instances: " + serviceInstances);
// 保持程序运行
while (true) {
Thread.sleep(1000);
}
}
}
通过以上步骤和示例代码,可以利用Zookeeper实现基本的服务注册与发现功能。