com.babyduncan.lock.LockingExample.java Source code

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Here is the source code for com.babyduncan.lock.LockingExample.java

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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 com.babyduncan.lock;

import com.google.common.io.Closeables;
import org.apache.curator.framework.CuratorFramework;
import org.apache.curator.framework.CuratorFrameworkFactory;
import org.apache.curator.retry.ExponentialBackoffRetry;

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 = "/locks";

    public static int i = 0;

    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);

        try {
            for (int i = 0; i < QTY; ++i) {
                final int index = i;
                Callable<Void> task = new Callable<Void>() {
                    @Override
                    public Void call() throws Exception {
                        CuratorFramework client = CuratorFrameworkFactory.newClient("localhost:2181",
                                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 (Throwable e) {
                            e.printStackTrace();
                        } finally {
                            Closeables.closeQuietly(client);
                        }
                        return null;
                    }
                };
                service.submit(task);
            }

            Thread.sleep(5000);

            System.out.println("result is " + i); // result is 250  ?i

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