content: /*
   * 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.datastax.oss.driver.internal.core.time;
  
  import static com.datastax.oss.driver.Assertions.assertThat;
  import static com.datastax.oss.driver.Assertions.assertThatStage;
  import static com.datastax.oss.driver.Assertions.fail;
  import static org.mockito.Mockito.when;
  
  import com.datastax.oss.driver.internal.core.util.concurrent.CompletableFutures;
  import java.util.List;
  import java.util.concurrent.CompletableFuture;
  import java.util.concurrent.CompletionStage;
  import java.util.concurrent.CopyOnWriteArrayList;
  import java.util.concurrent.ExecutorService;
  import java.util.concurrent.Executors;
  import java.util.concurrent.TimeUnit;
  import org.junit.Test;
  import org.mockito.stubbing.OngoingStubbing;
  
  public class ThreadLocalTimestampGeneratorTest extends MonotonicTimestampGeneratorTestBase {
    @Override
    protected MonotonicTimestampGenerator newInstance(Clock clock) {
      return new ThreadLocalTimestampGenerator(clock, context);
    }
  
    @Test
    public void should_confine_timestamps_to_thread() throws Exception {
      final int testThreadsCount = 2;
  
      // Prepare to generate 1000 timestamps for each thread, with the clock frozen at 1
      OngoingStubbing<Long> stub = when(clock.currentTimeMicros());
      for (int i = 0; i < testThreadsCount * 1000; i++) {
        stub = stub.thenReturn(1L);
      }
  
      MonotonicTimestampGenerator generator = newInstance(clock);
  
      List<CompletionStage<Void>> futures = new CopyOnWriteArrayList<>();
      ExecutorService executor = Executors.newFixedThreadPool(testThreadsCount);
      for (int i = 0; i < testThreadsCount; i++) {
        executor.submit(
            () -> {
              try {
                for (long l = 1; l <= 1000; l++) {
                  assertThat(generator.next()).isEqualTo(l);
                }
                futures.add(CompletableFuture.completedFuture(null));
              } catch (Throwable t) {
                futures.add(CompletableFutures.failedFuture(t));
              }
            });
      }
      executor.shutdown();
      if (!executor.awaitTermination(1, TimeUnit.SECONDS)) {
        fail("Expected executor to shut down cleanly");
      }
  
      assertThat(futures).hasSize(testThreadsCount);
      for (CompletionStage<Void> future : futures) {
        assertThatStage(future).isSuccess();
      }
    }
  }
  