// This should wake up waiter1 and cause the waiter1 node to be removed.
    waiter1.interrupt();

    waiter1.join();
    waiter2.awaitWaiting(); // should still be blocked

    LockSupport.unpark(waiter2); // spurious wakeup
    waiter2.awaitWaiting(); // should eventually re-park

    future.set(null);
    waiter2.join();
  }

    return new SingletonImmutableSet<>(element);
  }

  /*
   * TODO: b/315526394 - Skip the Builder entirely for the of(...) methods, since we don't need to
   * worry that we might trigger the fallback to the JDK-backed implementation? (The varargs one
   * _could_, so we could keep it as it is. Or we could convince ourselves that hash flooding is
   * unlikely in practice there, too.)
   */

  /**

                CollectionFeature.KNOWN_ORDER,
                MapFeature.REJECTS_DUPLICATES_AT_CREATION,
                CollectionFeature.ALLOWS_NULL_QUERIES)
            .named("ImmutableMap [JDK backed]")
            .createTestSuite());

    suite.addTest(
        MapTestSuiteBuilder.using(new ImmutableMapCopyOfGenerator())
            .withFeatures(
                CollectionSize.ANY,

     * recency queue. At write-time, or when the queue is full past the threshold, the queue will be
     * drained and the entries therein processed.
     *
     * <p>Note: locked reads should use {@link #recordLockedRead}.
     */
    void recordRead(ReferenceEntry<K, V> entry, long now) {
      if (map.recordsAccess()) {
        entry.setAccessTime(now);
      }

    ReentrantLock lockD = otherFactory.newReentrantLock("LockD");

    // lockA -> lockD
    lockA.lock();
    lockD.lock();
    lockA.unlock();
    lockD.unlock();

    // lockD -> lockA should fail even though lockD is from a different factory.
    lockD.lock();
    PotentialDeadlockException expected =

  private static final long SMALL_TIMEOUT_MILLIS = 10;

  /** How long to wait when determining that a thread is blocked if we expect it to be blocked. */
  private static final long EXPECTED_HANG_DELAY_MILLIS = 75;

  /**
   * How long to wait when determining that a thread is blocked if we DON'T expect it to be blocked.
   */
  private static final long UNEXPECTED_HANG_DELAY_MILLIS = 10000;

  /**

import com.google.common.collect.testing.SampleElements.Unhashables;
import com.google.common.collect.testing.UnhashableObject;
import java.util.Map;

@GwtIncompatible // GWT's ImmutableMap emulation is backed by java.util.HashMap.
public class SingletonImmutableMapWithUnhashableValueMapInterfaceTest
    extends RegularImmutableMapWithUnhashableValuesMapInterfaceTest {
  @Override

import com.google.common.collect.testing.SampleElements.Unhashables;
import com.google.common.collect.testing.UnhashableObject;
import java.util.Map;

@GwtIncompatible // GWT's ImmutableMap emulation is backed by java.util.HashMap.
public class RegularImmutableMapWithUnhashableValuesMapInterfaceTest
    extends AbstractImmutableMapMapInterfaceTest<Integer, UnhashableObject> {
  @Override

package com.google.common.base;

import com.google.common.annotations.GwtIncompatible;
import java.io.Serializable;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

/** A regex pattern implementation which is backed by the {@link Pattern}. */
@ElementTypesAreNonnullByDefault
@GwtIncompatible
final class JdkPattern extends CommonPattern implements Serializable {
  private final Pattern pattern;

  JdkPattern(Pattern pattern) {

 * limitations under the License.
 */

package com.google.common.graph;

import java.util.Set;
import javax.annotation.CheckForNull;

/**
 * A class to allow {@link ValueGraph} implementations to be backed by a provided delegate. This is
 * not currently planned to be released as a general-purpose forwarding class.
 *
 * @author James Sexton
 * @author Joshua O'Madadhain
 */
@ElementTypesAreNonnullByDefault