} finally {
      monitor.leave();
    }
  }

  @CanIgnoreReturnValue // pushed down from class to method
  @Override
  public @Nullable E peek() {
    Monitor monitor = this.monitor;
    monitor.enter();
    try {
      return q.peek();
    } finally {
      monitor.leave();
    }
  }

  /**

  }

  private static boolean isWindows() {
    return OS_NAME.value().startsWith("Windows");
  }

  /**
   * Test that verifies the resource leak fix for <a
   * href="https://github.com/google/guava/issues/5756">Issue #5756</a>.
   *
   * <p>This test covers a scenario where we write a smaller amount of data first, then write a

    assertThat(sepStopwatchA.get()).isNotNull();
    // Clear all references to the Stopwatch and wait for it to be gc'd.
    sepStopwatchA.set(null);
    GcFinalization.awaitClear(sepStopwatchRef.get());
    // Return a weak reference to the parallel ClassLoader. This is the reference that should
    // eventually become clear if there are no other references to the ClassLoader.
    return new WeakReference<ClassLoader>(sepLoader);
  }

  /**

        classStack.push(currentClass);
        action.run();
        classStack.pop();
    }

    private ClassMetaData getCurrentClass() {
        return classStack.peek();
    }

    private void visitExtendedTypes(NodeWithExtends<?> node) {
        ClassMetaData currentClass = getCurrentClass();
        for (ClassOrInterfaceType extendedType : node.getExtendedTypes()) {

func (c *LRU[K, V]) Contains(key K) (ok bool) {
	c.mu.Lock()
	defer c.mu.Unlock()
	_, ok = c.items[key]
	return ok
}

// Peek returns the key value (or undefined if not found) without updating
// the "recently used"-ness of the key.
func (c *LRU[K, V]) Peek(key K) (value V, ok bool) {
	c.mu.Lock()
	defer c.mu.Unlock()
	var ent *Entry[K, V]
	if ent, ok = c.items[key]; ok {
		// Expired item check

   */
  private boolean finalizeReference(Reference<?> reference, Method finalizeReferentMethod) {
    /*
     * This is for the benefit of phantom references. Weak and soft references will have already
     * been cleared by this point.
     */
    reference.clear();

    if (reference == frqReference) {
      /*

     * @return the generated key
     * @throws IOException if an I/O error occurs
     */
    protected abstract long makeKey(Request request) throws IOException;

    /**
     * Peek at the next key without removing it from the input stream
     *
     * @return the next key or null if none available
     * @throws IOException if an I/O error occurs
     */

      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
   * know that the background thread has stopped and released its strong reference.
   */
  private WeakReference<ReferenceQueue<Object>> queueReference;

    edge-case regression introduced with the events cleanup in 3.14.0.

 *  Fix: Provide actionable advice when the exchange is non-null. Prior to 3.14, OkHttp would
    silently leak connections when an interceptor retries without closing the response body. With
    3.14 we detect this problem but the exception was not helpful.

## Version 3.14.0

_2019-03-14_

          if (taskFuture.isDone()) {
            // Since the value of oldFuture can only ever be immediateVoidFuture() or setFuture of a
            // future that eventually came from immediateVoidFuture(), this doesn't leak throwables
            // or completion values.
            newFuture.setFuture(oldFuture);
          } else if (outputFuture.isCancelled() && taskExecutor.trySetCancelled()) {