private static final long SPIN_THRESHOLD_NANOS = 1000L;

  private static final AtomicHelper ATOMIC_HELPER;

  static {
    AtomicHelper helper;
    Throwable thrownUnsafeFailure = null;
    Throwable thrownAtomicReferenceFieldUpdaterFailure = null;

    try {
      helper = new UnsafeAtomicHelper();
    } catch (Exception | Error unsafeFailure) { // sneaky checked exception

 */

package com.google.common.collect.testing;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.google.common.collect.testing.Helpers.assertEqualIgnoringOrder;
import static com.google.common.collect.testing.Helpers.assertEqualInOrder;
import static com.google.common.collect.testing.Platform.format;
import static java.util.Arrays.asList;
import static java.util.Collections.unmodifiableSet;

import static java.util.Arrays.asList;
import static java.util.Comparator.comparing;
import static java.util.Comparator.naturalOrder;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.Helpers;
import com.google.common.testing.EqualsTester;
import java.util.Collections;
import java.util.Comparator;
import java.util.Optional;
import junit.framework.TestCase;

package com.google.common.collect;

import static com.google.common.truth.Truth.assertThat;
import static java.util.Arrays.asList;

import com.google.common.annotations.GwtCompatible;
import com.google.common.collect.testing.Helpers;
import com.google.common.testing.EqualsTester;
import java.util.Collections;
import java.util.Comparator;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

   *       MoreExecutors#newSequentialExecutor} wrapper around {@code directExecutor()}. More
   *       complex cases may require using thread pools or making deeper changes.)
   *   <li>If an exception propagates out of a {@code Runnable}, it is not necessarily seen by any
   *       {@code UncaughtExceptionHandler} for the thread. For example, if the callback passed to

        },
        (Multiset<E> multiset) -> copyOfSortedEntries(comparator, multiset.entrySet()));
  }

  @SuppressWarnings({"AndroidJdkLibsChecker", "Java7ApiChecker"})
  @IgnoreJRERequirement // helper for toImmutableSortedMultiset
  /*
   * If we make these calls inline inside toImmutableSortedMultiset, we get an Animal Sniffer error,
   * despite the @IgnoreJRERequirement annotation there. My assumption is that, because javac

  public static final String DATE = "Date";
  /** The HTTP {@code Pragma} header field name. */
  public static final String PRAGMA = "Pragma";
  /** The HTTP {@code Via} header field name. */
  public static final String VIA = "Via";
  /** The HTTP {@code Warning} header field name. */
  public static final String WARNING = "Warning";

  // HTTP Request header fields