import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.atomic.AtomicReferenceArray;
import org.jspecify.annotations.Nullable;

/**
 * Static utility methods pertaining to classes in the {@code java.util.concurrent.atomic} package.
 *
 * @author Kurt Alfred Kluever
 * @since 10.0
 */
@GwtIncompatible
public final class Atomics {
  private Atomics() {}

  /**

  private static final Object OBJECT = new Object();

  public void testNewReference() throws Exception {
    assertThat(Atomics.newReference().get()).isNull();
  }

  public void testNewReference_withInitialValue() throws Exception {
    assertThat(Atomics.newReference(null).get()).isNull();
    assertEquals(OBJECT, Atomics.newReference(OBJECT).get());
  }

  public void testNewReferenceArray_withLength() throws Exception {

  private static final Object OBJECT = new Object();

  public void testNewReference() throws Exception {
    assertThat(Atomics.newReference().get()).isNull();
  }

  public void testNewReference_withInitialValue() throws Exception {
    assertThat(Atomics.newReference(null).get()).isNull();
    assertEquals(OBJECT, Atomics.newReference(OBJECT).get());
  }

  public void testNewReferenceArray_withLength() throws Exception {

    long bitSize() {
      return (long) data.length() * Long.SIZE;
    }

    /**
     * Number of set bits (1s).
     *
     * <p>Note that because of concurrent set calls and uses of atomics, this bitCount is a (very)
     * close *estimate* of the actual number of bits set. It's not possible to do better than an
     * estimate without locking. Note that the number, if not exactly accurate, is *always*

   *
   * Table entries are of class Cell; a variant of AtomicLong padded
   * to reduce cache contention on most processors. Padding is
   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each
   * other. But Atomic objects residing in arrays will tend to be
   * placed adjacent to each other, and so will most often share

   *
   * Table entries are of class Cell; a variant of AtomicLong padded
   * to reduce cache contention on most processors. Padding is
   * overkill for most Atomics because they are usually irregularly
   * scattered in memory and thus don't interfere much with each
   * other. But Atomic objects residing in arrays will tend to be
   * placed adjacent to each other, and so will most often share

 * generated today may <i>not</i> be readable by a binary that was compiled 6 months ago).
 *
 * <p>As of Guava 23.0, this class is thread-safe and lock-free. It internally uses atomics and
 * compare-and-swap to ensure correctness when multiple threads are used to access it.
 *
 * @param <T> the type of instances that the {@code BloomFilter} accepts
 * @author Dimitris Andreou
 * @author Kevin Bourrillion

twice.
</p>

<h3 id="atomic">Atomic Values</h3>

<p>
The APIs in the <a href="/pkg/sync/atomic/"><code>sync/atomic</code></a>
package are collectively “atomic operations”
that can be used to synchronize the execution of different goroutines.
If the effect of an atomic operation <i>A</i> is observed by atomic operation <i>B</i>,
then <i>A</i> is synchronized before <i>B</i>.

import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.LockSupport;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;

import java.util.concurrent.Future;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import java.util.concurrent.atomic.AtomicReference;
import java.util.concurrent.locks.LockSupport;
import junit.framework.AssertionFailedError;
import junit.framework.TestCase;