-keepclassmembers class com.google.common.base.internal.Finalizer {
  *** startFinalizer(...);
}
-keepnames class com.google.common.base.FinalizableReference {
  void finalizeReferent();
}
-keepclassmembers class com.google.common.base.FinalizableReference {
  void finalizeReferent();

    volatile boolean finalizeReferentCalled;

    MockReference(FinalizableReferenceQueue frq) {
      super(new Object(), frq);
    }

    @Override
    public void finalizeReferent() {
      finalizeReferentCalled = true;
    }
  }

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we

 * {@link FinalizableReference#finalizeReferent()} on them. Java 9+ users should prefer {@link
 * java.lang.ref.Cleaner Cleaner}; see example <a href="#cleaner">below</a>.
 *
 * <p>Keep a strong reference to this object until all of the associated referents have been
 * finalized. If this object is garbage collected earlier, the backing thread will not invoke {@code
 * finalizeReferent()} on the remaining references.
 *

      ReferenceQueue<Object> queue,
      PhantomReference<Object> frqReference) {
    /*
     * We use FinalizableReference.class for two things:
     *
     * 1) To invoke FinalizableReference.finalizeReferent()
     *
     * 2) To detect when FinalizableReference's class loader has to be garbage collected, at which
     * point, Finalizer can stop running
     */

import com.google.common.annotations.J2ktIncompatible;
import java.lang.ref.ReferenceQueue;
import java.lang.ref.WeakReference;
import org.jspecify.annotations.Nullable;

/**
 * Weak reference with a {@code finalizeReferent()} method which a background thread invokes after
 * the garbage collector reclaims the referent. This is a simpler alternative to using a {@link
 * ReferenceQueue}.
 *
 * @author Bob Lee
 * @since 2.0
 */

   * restrictions prevented starting a background thread, in which case this method is invoked when
   * new references are created.
   */
  void finalizeReferent();

import com.google.common.annotations.J2ktIncompatible;
import java.lang.ref.PhantomReference;
import java.lang.ref.ReferenceQueue;
import org.jspecify.annotations.Nullable;

/**
 * Phantom reference with a {@code finalizeReferent()} method which a background thread invokes
 * after the garbage collector reclaims the referent. This is a simpler alternative to using a
 * {@link ReferenceQueue}.
 *

    public MyFinalizableWeakReference(Object x, FinalizableReferenceQueue queue) {
      super(x, queue);
    }

    @Override
    public void finalizeReferent() {}
  }

  private WeakReference<ClassLoader> useFrqInSeparateLoader() throws Exception {
    ClassLoader myLoader = getClass().getClassLoader();