| /** |
| * 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.curator.framework.imps; |
| |
| import org.apache.curator.RetryLoop; |
| import org.apache.curator.TimeTrace; |
| import org.apache.curator.framework.api.BackgroundCallback; |
| import org.apache.curator.framework.api.BackgroundPathable; |
| import org.apache.curator.framework.api.CuratorEvent; |
| import org.apache.curator.framework.api.CuratorEventType; |
| import org.apache.curator.framework.api.CuratorWatcher; |
| import org.apache.curator.framework.api.ExistsBuilder; |
| import org.apache.curator.framework.api.ExistsBuilderMain; |
| import org.apache.curator.framework.api.Pathable; |
| import org.apache.curator.utils.ZKPaths; |
| import org.apache.zookeeper.AsyncCallback; |
| import org.apache.zookeeper.KeeperException; |
| import org.apache.zookeeper.Watcher; |
| import org.apache.zookeeper.data.Stat; |
| import java.util.concurrent.Callable; |
| import java.util.concurrent.Executor; |
| |
| class ExistsBuilderImpl implements ExistsBuilder, BackgroundOperation<String> |
| { |
| private final CuratorFrameworkImpl client; |
| private Backgrounding backgrounding; |
| private Watching watching; |
| private boolean createParentContainersIfNeeded; |
| |
| ExistsBuilderImpl(CuratorFrameworkImpl client) |
| { |
| this.client = client; |
| backgrounding = new Backgrounding(); |
| watching = new Watching(); |
| createParentContainersIfNeeded = false; |
| } |
| |
| @Override |
| public ExistsBuilderMain creatingParentContainersIfNeeded() |
| { |
| createParentContainersIfNeeded = true; |
| return this; |
| } |
| |
| @Override |
| public BackgroundPathable<Stat> watched() |
| { |
| watching = new Watching(true); |
| return this; |
| } |
| |
| @Override |
| public BackgroundPathable<Stat> usingWatcher(Watcher watcher) |
| { |
| watching = new Watching(client, watcher); |
| return this; |
| } |
| |
| @Override |
| public BackgroundPathable<Stat> usingWatcher(CuratorWatcher watcher) |
| { |
| watching = new Watching(client, watcher); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground(BackgroundCallback callback, Object context) |
| { |
| backgrounding = new Backgrounding(callback, context); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground(BackgroundCallback callback, Object context, Executor executor) |
| { |
| backgrounding = new Backgrounding(client, callback, context, executor); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground(BackgroundCallback callback) |
| { |
| backgrounding = new Backgrounding(callback); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground(BackgroundCallback callback, Executor executor) |
| { |
| backgrounding = new Backgrounding(client, callback, executor); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground() |
| { |
| backgrounding = new Backgrounding(true); |
| return this; |
| } |
| |
| @Override |
| public Pathable<Stat> inBackground(Object context) |
| { |
| backgrounding = new Backgrounding(context); |
| return this; |
| } |
| |
| @Override |
| public void performBackgroundOperation(final OperationAndData<String> operationAndData) throws Exception |
| { |
| final TimeTrace trace = client.getZookeeperClient().startTracer("ExistsBuilderImpl-Background"); |
| AsyncCallback.StatCallback callback = new AsyncCallback.StatCallback() |
| { |
| @Override |
| public void processResult(int rc, String path, Object ctx, Stat stat) |
| { |
| trace.commit(); |
| CuratorEvent event = new CuratorEventImpl(client, CuratorEventType.EXISTS, rc, path, null, ctx, stat, null, null, null, null, null); |
| client.processBackgroundOperation(operationAndData, event); |
| } |
| }; |
| if ( watching.isWatched() ) |
| { |
| client.getZooKeeper().exists(operationAndData.getData(), true, callback, backgrounding.getContext()); |
| } |
| else |
| { |
| client.getZooKeeper().exists(operationAndData.getData(), watching.getWatcher(client, operationAndData.getData()), callback, backgrounding.getContext()); |
| } |
| } |
| |
| @Override |
| public Stat forPath(String path) throws Exception |
| { |
| path = client.fixForNamespace(path); |
| |
| Stat returnStat = null; |
| if ( backgrounding.inBackground() ) |
| { |
| OperationAndData<String> operationAndData = new OperationAndData<String>(this, path, backgrounding.getCallback(), null, backgrounding.getContext()); |
| if ( createParentContainersIfNeeded ) |
| { |
| CreateBuilderImpl.backgroundCreateParentsThenNode(client, operationAndData, operationAndData.getData(), backgrounding, true); |
| } |
| else |
| { |
| client.processBackgroundOperation(operationAndData, null); |
| } |
| } |
| else |
| { |
| returnStat = pathInForeground(path); |
| } |
| |
| return returnStat; |
| } |
| |
| private Stat pathInForeground(final String path) throws Exception |
| { |
| if ( createParentContainersIfNeeded ) |
| { |
| final String parent = ZKPaths.getPathAndNode(path).getPath(); |
| if ( !parent.equals(ZKPaths.PATH_SEPARATOR) ) |
| { |
| TimeTrace trace = client.getZookeeperClient().startTracer("ExistsBuilderImpl-Foreground-CreateParents"); |
| RetryLoop.callWithRetry |
| ( |
| client.getZookeeperClient(), |
| new Callable<Void>() |
| { |
| @Override |
| public Void call() throws Exception |
| { |
| try |
| { |
| ZKPaths.mkdirs(client.getZooKeeper(), parent, true, client.getAclProvider(), true); |
| } |
| catch ( KeeperException e ) |
| { |
| // ignore |
| } |
| return null; |
| } |
| } |
| ); |
| trace.commit(); |
| } |
| } |
| return pathInForegroundStandard(path); |
| } |
| |
| private Stat pathInForegroundStandard(final String path) throws Exception |
| { |
| TimeTrace trace = client.getZookeeperClient().startTracer("ExistsBuilderImpl-Foreground"); |
| Stat returnStat = RetryLoop.callWithRetry |
| ( |
| client.getZookeeperClient(), |
| new Callable<Stat>() |
| { |
| @Override |
| public Stat call() throws Exception |
| { |
| Stat returnStat; |
| if ( watching.isWatched() ) |
| { |
| returnStat = client.getZooKeeper().exists(path, true); |
| } |
| else |
| { |
| returnStat = client.getZooKeeper().exists(path, watching.getWatcher(client, path)); |
| } |
| return returnStat; |
| } |
| } |
| ); |
| trace.commit(); |
| return returnStat; |
| } |
| } |