* from GC, as with {@link #awaitClear}. Because there are no guarantees for the order of GC
   * finalization processing, there may still be some unfinished work for the GC to do after this
   * method returns.
   *
   * <p>This method does not create any memory pressure as would be required to cause soft
   * references to be processed.
   *

   * from GC, as with {@link #awaitClear}. Because there are no guarantees for the order of GC
   * finalization processing, there may still be some unfinished work for the GC to do after this
   * method returns.
   *
   * <p>This method does not create any memory pressure as would be required to cause soft
   * references to be processed.
   *

    } catch (NoSuchElementException expected) {
    }
  }


  @J2ktIncompatible // weak references, details of GC
  @GwtIncompatible // weak references
  @AndroidIncompatible // depends on details of GC
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {

      RunnableExecutorPair list;
      synchronized (this) {
        if (executed) {
          return;
        }
        executed = true;
        list = runnables;
        runnables = null; // allow GC to free listeners even if this stays around for a while.
      }
      while (list != null) {
        executeListener(list.runnable, list.executor);
        list = list.next;
      }
    }

    assertThat(Enums.getIfPresent(TestEnum.class, "WOMBAT")).isAbsent();
  }


  @J2ktIncompatible
  @GwtIncompatible // weak references
  @AndroidIncompatible // depends on details of GC and classloading
  public void testGetIfPresent_doesNotPreventClassUnloading() throws Exception {
    WeakReference<?> shadowLoaderReference = doTestClassUnloading();
    GcFinalization.awaitClear(shadowLoaderReference);
  }

import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link FinalizableReferenceQueue}.
 *
 * @author Bob Lee
 */
// - depends on details of GC and classloading
// - .class files aren't available
// - possibly no real concept of separate ClassLoaders?
@AndroidIncompatible
@GwtIncompatible
public class FinalizableReferenceQueueTest extends TestCase {

import junit.framework.TestCase;
import org.checkerframework.checker.nullness.qual.Nullable;

/**
 * Unit test for {@link FinalizableReferenceQueue}.
 *
 * @author Bob Lee
 */
// - depends on details of GC and classloading
// - .class files aren't available
// - possibly no real concept of separate ClassLoaders?
@AndroidIncompatible
@GwtIncompatible
public class FinalizableReferenceQueueTest extends TestCase {

      fail("No exception thrown");
    } catch (UnsupportedOperationException expected) {
    }
  }


  @GwtIncompatible // weak references
  @J2ktIncompatible
  @AndroidIncompatible // depends on details of GC
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {
            return new Object();

      fail("No exception thrown");
    } catch (UnsupportedOperationException expected) {
    }
  }


  @GwtIncompatible // weak references
  @J2ktIncompatible
  @AndroidIncompatible // depends on details of GC
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {
            return new Object();

    } catch (NoSuchElementException expected) {
    }
  }


  @J2ktIncompatible // weak references, details of GC
  @GwtIncompatible // weak references
  @AndroidIncompatible // depends on details of GC
  public void testFreesNextReference() {
    Iterator<Object> itr =
        new AbstractIterator<Object>() {
          @Override
          public Object computeNext() {