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Example usages of various Curator features.
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/**
 * 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 locking;

import org.apache.curator.utils.CloseableUtils;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;
import org.apache.curator.test.TestingServer;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.TimeUnit;

public class LockingExample
{
    private static final int        QTY = 5;
    private static final int        REPETITIONS = QTY * 10;

    private static final String     PATH = "/examples/locks";

    public static void main(String[] args) throws Exception
    {
        // all of the useful sample code is in ExampleClientThatLocks.java

        // FakeLimitedResource simulates some external resource that can only be access by one process at a time
        final FakeLimitedResource   resource = new FakeLimitedResource();

        ExecutorService             service = Executors.newFixedThreadPool(QTY);
        final TestingServer         server = new TestingServer();
        try
        {
            for ( int i = 0; i < QTY; ++i )
            {
                final int       index = i;
                Callable  task = new Callable()
                {
                    @Override
                    public Void call() throws Exception
                    {
                        CuratorFramework        client = CuratorFrameworkFactory.newClient(server.getConnectString(), new ExponentialBackoffRetry(1000, 3));
                        try
                        {
                            client.start();

                            ExampleClientThatLocks      example = new ExampleClientThatLocks(client, PATH, resource, "Client " + index);
                            for ( int j = 0; j < REPETITIONS; ++j )
                            {
                                example.doWork(10, TimeUnit.SECONDS);
                            }
                        }
                        catch ( InterruptedException e )
                        {
                            Thread.currentThread().interrupt();
                        }
                        catch ( Exception e )
                        {
                            e.printStackTrace();
                            // log or do something
                        }
                        finally
                        {
                            CloseableUtils.closeQuietly(client);
                        }
                        return null;
                    }
                };
                service.submit(task);
            }

            service.shutdown();
            service.awaitTermination(10, TimeUnit.MINUTES);
        }
        finally
        {
            CloseableUtils.closeQuietly(server);
        }
    }
}