samza-core/src/test/java/org/apache/samza/executors/TestKeyBasedExecutorService.java

/*
 * 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.samza.executors;

import junit.framework.Assert;
import org.junit.Test;

import java.util.Iterator;
import java.util.concurrent.ConcurrentLinkedQueue;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.TimeUnit;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class TestKeyBasedExecutorService {

  @Test
  public void testSubmitOrdered() {
    KeyBasedExecutorService executorService = new KeyBasedExecutorService("test", 2);
    ConcurrentLinkedQueue<Integer> resultFromThread0 = new ConcurrentLinkedQueue<>();
    ConcurrentLinkedQueue<Integer> resultFromThread1 = new ConcurrentLinkedQueue<>();

    final CountDownLatch shutdownLatch = new CountDownLatch(10);

    for (int i = 0; i < 10; i++) {
      final int currentStep = i;
      executorService.submitOrdered(currentStep, new Runnable() {
        @Override
        public void run() {
          String threadName = Thread.currentThread().getName();
          Pattern compiledPattern = Pattern.compile("test-(.+)-0");
          Matcher matcher = compiledPattern.matcher(threadName);
          if (matcher.find()) {
            String threadPoolNumber = matcher.group(1);
            if ("0".equals(threadPoolNumber)) {
              resultFromThread0.add(currentStep);
            } else if ("1".equals(threadPoolNumber)) {
              resultFromThread1.add(currentStep);
            }
            shutdownLatch.countDown();
          }
        }
      });
    }
    try {
      shutdownLatch.await(2, TimeUnit.SECONDS);
      executorService.shutdown();
    } catch (InterruptedException e) {
      e.printStackTrace();
    }
    Assert.assertEquals(5, resultFromThread0.size());
    Assert.assertEquals(5, resultFromThread1.size());

    Iterator<Integer> iterator = resultFromThread0.iterator();
    int i = 0;
    while (iterator.hasNext()) {
      Assert.assertEquals(i, iterator.next().intValue());
      i += 2;
    }
    iterator = resultFromThread1.iterator();
    i = 1;
    while (iterator.hasNext()) {
      Assert.assertEquals(i, iterator.next().intValue());
      i += 2;
    }

  }
}