}

  @GwtIncompatible // java.lang.ref.WeakReference
  private static final Map<Class<? extends Enum<?>>, Map<String, WeakReference<? extends Enum<?>>>>
      enumConstantCache = new WeakHashMap<>();

  @GwtIncompatible // java.lang.ref.WeakReference
  private static <T extends Enum<T>> Map<String, WeakReference<? extends Enum<?>>> populateCache(
      Class<T> enumClass) {
    Map<String, WeakReference<? extends Enum<?>>> result = new HashMap<>();

    GcFinalization.awaitDone(future);
    assertTrue(future.isDone());
    assertTrue(future.isCancelled());
  }

  public void testAwaitClear() {
    final WeakReference<Object> ref = new WeakReference<>(new Object());
    GcFinalization.awaitClear(ref);
    assertNull(ref.get());
  }

  public void testAwaitDone_finalizationPredicate() {

    GcFinalization.awaitDone(future);
    assertTrue(future.isDone());
    assertTrue(future.isCancelled());
  }

  public void testAwaitClear() {
    final WeakReference<Object> ref = new WeakReference<>(new Object());
    GcFinalization.awaitClear(ref);
    assertNull(ref.get());
  }

  public void testAwaitDone_finalizationPredicate() {

    Integer canonical = new Integer(5);
    Integer not = new Integer(5);

    Interner<Integer> pool = Interners.newWeakInterner();
    assertSame(canonical, pool.intern(canonical));

    WeakReference<Integer> signal = new WeakReference<>(canonical);
    canonical = null; // Hint to the JIT that canonical is unreachable

    GcFinalization.awaitClear(signal);
    assertSame(not, pool.intern(not));
  }

    WeakReference<? extends Enum<?>> ref = Enums.getEnumConstants(enumClass).get(value);
    /*
     * We use `fromNullable` instead of `of` because `WeakReference.get()` has a nullable return
     * type.
     *
     * In practice, we are very unlikely to see `null`: The `WeakReference` to the enum constant

  }

  @GwtIncompatible // java.lang.ref.WeakReference
  private static final Map<Class<? extends Enum<?>>, Map<String, WeakReference<? extends Enum<?>>>>
      enumConstantCache = new WeakHashMap<>();

  @GwtIncompatible // java.lang.ref.WeakReference
  private static <T extends Enum<T>> Map<String, WeakReference<? extends Enum<?>>> populateCache(
      Class<T> enumClass) {
    Map<String, WeakReference<? extends Enum<?>>> result = new HashMap<>();

import com.google.common.annotations.GwtIncompatible;
import com.google.common.base.internal.Finalizer;
import com.google.common.testing.GcFinalization;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import java.net.URL;
import java.net.URLClassLoader;
import java.util.Arrays;
import java.util.Collections;
import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**

  public void testStrongImplementations() {
    for (Striped<?> striped : strongImplementations()) {
      WeakReference<Object> weakRef = new WeakReference<>(striped.get(new Object()));
      WeakReference<Object> garbage = new WeakReference<>(new Object());
      GcFinalization.awaitClear(garbage);
      assertNotNull(weakRef.get());
    }
  }

  public void testMaximalWeakStripedLock() {

  public void testStrongImplementations() {
    for (Striped<?> striped : strongImplementations()) {
      WeakReference<Object> weakRef = new WeakReference<>(striped.get(new Object()));
      WeakReference<Object> garbage = new WeakReference<>(new Object());
      GcFinalization.awaitClear(garbage);
      assertNotNull(weakRef.get());
    }
  }

  public void testMaximalWeakStripedLock() {

    Integer canonical = new Integer(5);
    Integer not = new Integer(5);

    Interner<Integer> pool = Interners.newWeakInterner();
    assertSame(canonical, pool.intern(canonical));

    WeakReference<Integer> signal = new WeakReference<>(canonical);
    canonical = null; // Hint to the JIT that canonical is unreachable

    GcFinalization.awaitClear(signal);
    assertSame(not, pool.intern(not));
  }