| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package org.apache.twill.zookeeper; |
| |
| import org.apache.twill.internal.zookeeper.FailureRetryZKClient; |
| import org.apache.twill.internal.zookeeper.NamespaceZKClient; |
| import org.apache.twill.internal.zookeeper.RewatchOnExpireZKClient; |
| |
| /** |
| * Utility class to create {@link ZKClient} instances. |
| */ |
| public final class ZKClients { |
| |
| /** |
| * Creates a {@link ZKClient} that will perform auto re-watch on all existing watches |
| * when reconnection happens after session expiration. All {@link org.apache.zookeeper.Watcher Watchers} |
| * set through the returned {@link ZKClient} would not receive any connection events. |
| * |
| * @param client The {@link ZKClient} for operations delegation. |
| * @return A {@link ZKClient} that will do auto re-watch on all methods that accept a |
| * {@link org.apache.zookeeper.Watcher} upon session expiration. |
| */ |
| public static ZKClient reWatchOnExpire(ZKClient client) { |
| return new RewatchOnExpireZKClient(client); |
| } |
| |
| /** |
| * Creates a {@link ZKClient} that will retry interim failure (e.g. connection loss, session expiration) |
| * based on the given {@link RetryStrategy}. |
| * |
| * @param client The {@link ZKClient} for operations delegation. |
| * @param retryStrategy The {@link RetryStrategy} to be invoke when there is operation failure. |
| * @return A {@link ZKClient}. |
| */ |
| public static ZKClient retryOnFailure(ZKClient client, RetryStrategy retryStrategy) { |
| return new FailureRetryZKClient(client, retryStrategy); |
| } |
| |
| /** |
| * Creates a {@link ZKClient} that will add prefix namespace for every paths. |
| * |
| * @param zkClient The {@link ZKClient} for operations delegation. |
| * @param namespace The prefix namespace to be prepended to paths. |
| * @return A {@link ZKClient} that will add namespace to every path. |
| */ |
| public static ZKClient namespace(ZKClient zkClient, String namespace) { |
| return new NamespaceZKClient(zkClient, namespace); |
| } |
| |
| private ZKClients() { |
| } |
| } |