import static junit.framework.Assert.assertTrue;
import static junit.framework.Assert.fail;
import static org.junit.Assert.assertThrows;

import java.util.concurrent.CancellationException;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.ExecutorService;
import org.jspecify.annotations.NullUnmarked;
import org.jspecify.annotations.Nullable;

/**

 * the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.truth.Truth.assertThat;
import static com.google.common.util.concurrent.Futures.getDone;
import static com.google.common.util.concurrent.Futures.immediateCancelledFuture;
import static com.google.common.util.concurrent.Futures.immediateFailedFuture;
import static com.google.common.util.concurrent.Futures.immediateFuture;

import java.util.List;
import java.util.concurrent.ArrayBlockingQueue;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingDeque;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.PriorityBlockingQueue;

 */

package com.google.common.util.concurrent;

import static com.google.common.util.concurrent.MoreExecutors.directExecutor;
import static java.util.concurrent.Executors.newCachedThreadPool;
import static java.util.concurrent.TimeUnit.SECONDS;

import com.google.common.testing.NullPointerTester;
import java.util.concurrent.CountDownLatch;
import java.util.concurrent.Executor;
import java.util.concurrent.atomic.AtomicInteger;

 */

package com.google.common.util.concurrent;

import static java.lang.Math.min;
import static java.util.concurrent.TimeUnit.NANOSECONDS;

import com.google.common.annotations.GwtIncompatible;
import com.google.common.annotations.J2ktIncompatible;
import com.google.errorprone.annotations.CanIgnoreReturnValue;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;

 * limitations under the License.
 */

package com.google.common.util.concurrent;

import static com.google.common.truth.Truth.assertThat;
import static java.util.concurrent.TimeUnit.MILLISECONDS;
import static org.junit.Assert.assertThrows;

import java.util.concurrent.Callable;
import java.util.concurrent.ExecutionException;
import junit.framework.TestCase;
import org.jspecify.annotations.NullUnmarked;

 */

package com.google.common.util.concurrent;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.util.concurrent.FuturesTest.pseudoTimedGetUninterruptibly;
import static com.google.common.util.concurrent.Uninterruptibles.getUninterruptibly;
import static java.util.concurrent.TimeUnit.MILLISECONDS;

import static java.lang.Math.min;
import static java.util.concurrent.Executors.newFixedThreadPool;

import com.google.common.base.Function;
import com.google.common.primitives.Ints;
import java.util.List;
import java.util.Random;
import java.util.concurrent.Callable;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ConcurrentMap;
import java.util.concurrent.ConcurrentSkipListMap;

<img src="/img/async/concurrent-burgers/concurrent-burgers-02.png" class="illustration">

El cajero dice algo al cocinero en la cocina para que sepan que tienen que preparar tus hamburguesas (aunque actualmente están preparando las de los clientes anteriores).

<img src="/img/async/concurrent-burgers/concurrent-burgers-03.png" class="illustration">

Pagas. 💸

El cajero te da el número de tu turno.

  public void decrement() {
    add(-1L);
  }

  /**
   * Returns the current sum. The returned value is NOT an atomic snapshot; invocation in
   * the absence of concurrent updates returns an accurate result, but concurrent updates that occur
   * while the sum is being calculated might not be incorporated.
   *
   * @return the sum
   */
  @Override
  public long sum() {
    long sum = base;