| /** |
| * 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.camel.component.zookeeper.operations; |
| |
| import java.util.Set; |
| import java.util.concurrent.CopyOnWriteArraySet; |
| import java.util.concurrent.ExecutionException; |
| import java.util.concurrent.TimeUnit; |
| import java.util.concurrent.TimeoutException; |
| |
| import org.apache.zookeeper.ZooKeeper; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| /** |
| * <code>ZooKeeperOperation</code> is the base class for wrapping various |
| * ZooKeeper API instructions and callbacks into callable and composable operation |
| * objects. |
| */ |
| public abstract class ZooKeeperOperation<ResultType> { |
| |
| protected static final Logger LOG = LoggerFactory.getLogger(ZooKeeperOperation.class); |
| |
| protected static final Class<?>[] CONSTRUCTOR_ARGS = {ZooKeeper.class, String.class}; |
| |
| protected String node; |
| |
| protected ZooKeeper connection; |
| |
| protected Set<Thread> waitingThreads = new CopyOnWriteArraySet<Thread>(); |
| |
| protected OperationResult<ResultType> result; |
| |
| private boolean producesExchange; |
| |
| private boolean cancelled; |
| |
| public ZooKeeperOperation(ZooKeeper connection, String node) { |
| this(connection, node, true); |
| } |
| |
| public ZooKeeperOperation(ZooKeeper connection, String node, boolean producesExchange) { |
| this.connection = connection; |
| this.node = node; |
| this.producesExchange = producesExchange; |
| } |
| |
| /** |
| * Gets the result of this zookeeper operation, i.e. some data and the |
| * associated node stats |
| */ |
| public abstract OperationResult<ResultType> getResult(); |
| |
| public OperationResult<ResultType> get() throws InterruptedException, ExecutionException { |
| waitingThreads.add(Thread.currentThread()); |
| result = getResult(); |
| return result; |
| } |
| |
| public OperationResult<ResultType> get(long timeout, TimeUnit unit) throws InterruptedException, ExecutionException, TimeoutException { |
| // TODO perhaps set a timer here |
| return get(); |
| } |
| |
| public boolean cancel(boolean mayInterruptIfRunning) { |
| if (mayInterruptIfRunning) { |
| for (Thread waiting : waitingThreads) { |
| waiting.interrupt(); |
| } |
| cancelled = true; |
| } |
| return mayInterruptIfRunning; |
| } |
| |
| public boolean isCancelled() { |
| return cancelled; |
| } |
| |
| public boolean isDone() { |
| return result != null; |
| } |
| |
| public String getNode() { |
| return node; |
| } |
| |
| public boolean shouldProduceExchange() { |
| return producesExchange; |
| } |
| |
| // TODO slightly different to a clone as it uses the constructor |
| public ZooKeeperOperation<?> createCopy() throws Exception { |
| return getClass().getConstructor(CONSTRUCTOR_ARGS).newInstance(new Object[] {connection, node}); |
| } |
| } |