new TearDown() {

          @Override
          public void tearDown() throws Exception {
            synchronized (result.lock) {
              assertEquals(
                  "The test should have cleared the stack (say, by virtue of running runTearDown)",
                  0,
                  result.stack.size());
            }
          }
        });
    return result;
  }

        break;
      }
      try {
        Thread.sleep(10);
      } catch (InterruptedException e) {
        /* ignore */
      }
      try {
        // Fill up heap so soft references get cleared.
        filler = new byte[max(filler.length, filler.length * 2)];
      } catch (OutOfMemoryError e) {
      }
    }

    CacheTesting.processPendingNotifications(cache);
    assertEquals(1, cache.size());

    }

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

  /**
   * Keeps a weak reference to the underlying reference queue. When this reference is cleared, we
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;


  public void testThatFinalizerStops() {

         * Run at the beginning of each build. Kill potentially leaked processes in previous builds.
         * Only kill local Gradle processes (classpath in checkout directory).
         * Not clean up global Gradle processes (i.e. classpath in ~/.gradle/...).
         */
        KILL_LEAKED_PROCESSES_FROM_PREVIOUS_BUILDS,
        /**
         * Run at the end of each build. Kill potentially leaked processes in the current build.

     * 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
     * won't be cleared as long as the enum constant is referenced somewhere, and the enum constant
     * is referenced somewhere for as long as the enum class is loaded. *Maybe in theory* the enum

   * has consumed the entire input and they are ready to output a {@code HashCode}. The order of the
   * hashers are the same order as the functions given to the constructor.
   */
  // this could be cleaner if it passed HashCode[], but that would create yet another array...
  /* protected */ abstract HashCode makeHash(Hasher[] hashers);

  @Override
  public Hasher newHasher() {

       * pass.
       *
       * 2. We would probably choose to compare exceptions using == instead of equals() (for
       * consistency with how weak references are cleared). That's a behavior change -- arguably the
       * removal of a feature.
       *
       * Fortunately, exceptions rarely contain references to expensive resources.
       */

      //

  // new ClassLoader. If Enums.getIfPresent does caching that prevents the shadow TestEnum
  // (and therefore its ClassLoader) from being unloaded, then this WeakReference will never be
  // cleared.
  @J2ktIncompatible
  @GwtIncompatible // weak references
  private WeakReference<?> doTestClassUnloading() throws Exception {
    URLClassLoader shadowLoader = new URLClassLoader(getClassPathUrls(), null);

   *   <li>{@link #JAVA_COMPILER}, while still listed as required as of Java 15, is typically not
   *       available even under older version.
   *   <li>Any property may be cleared through APIs like {@link System#clearProperty}.
   *   <li>Unusual environments like GWT may have their own special handling of system properties.
   * </ul>
   *

     *   <li>If this field's value == null because it originally belonged to another thread and that
     *       thread cleared it, we still know that it's not associated with our thread
     *   <li>If this field's value == null because it was associated with our thread and was
     *       cleared, we know that we're not executing inline any more
     * </ul>
     *