assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(writeLockA.tryLock());
    assertFalse(readLockA.tryLock());

    thread.releaseLockAndFinish();

    assertFalse(lockA.tryLock());

    thread.releaseLockAndFinish();
    assertTrue(lockA.tryLock());
  }

  public void testReentrantWriteLock_tryLock() throws Exception {
    LockingThread thread = new LockingThread(writeLockA);
    thread.start();

    thread.waitUntilHoldingLock();
    assertFalse(writeLockA.tryLock());
    assertFalse(readLockA.tryLock());

    thread.releaseLockAndFinish();

        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
  }

  /**
   * Invokes {@code lock.}{@link Lock#tryLock(long, TimeUnit) tryLock(timeout, unit)}
   * uninterruptibly.
   *
   * @since NEXT (but since 30.0 in the JRE flavor)
   */
  @J2ktIncompatible
  @GwtIncompatible // concurrency
  @SuppressWarnings("Java7ApiChecker")

        }
      }
    } finally {
      if (interrupted) {
        Thread.currentThread().interrupt();
      }
    }
  }

  /**
   * Invokes {@code lock.}{@link Lock#tryLock(long, TimeUnit) tryLock(timeout, unit)}
   * uninterruptibly.
   *
   * @since 30.0 (but only since 33.4.0 in the Android flavor)
   */
  @J2ktIncompatible
  @GwtIncompatible // concurrency

		return *v, nil
	}

	// Fetch new value asynchronously, while we do not return an error
	// if v != nil value or
	if t.opts.NoWait && v != nil && tNow-vTime < ttl.Milliseconds()*2 {
		if t.updating.TryLock() {
			go func() {
				defer t.updating.Unlock()
				t.update(context.Background())
			}()
		}
		return *v, nil
	}

	// Get lock. Either we get it or we wait for it.
	t.updating.Lock()

    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {
    for (Striped<?> striped : strongImplementations()) {

    WeakReference<Object> garbage = new WeakReference<>(new Object());
    GcFinalization.awaitClear(garbage);
    Lock writeLock = striped.get(key).writeLock();
    readLock.lock();
    assertFalse(writeLock.tryLock());
    readLock.unlock();
  }

  @AndroidIncompatible // Presumably GC doesn't trigger, despite our efforts.
  public void testStrongImplementations() {
    for (Striped<?> striped : strongImplementations()) {

		gridLogIf(m.ctx, err)
		m.closeLocked()
		return false
	}
}

func (m *muxClient) close() {
	if debugPrint {
		fmt.Println("closing outgoing mux", m.MuxID)
	}
	if !m.respMu.TryLock() {
		// Cancel before locking - will unblock any pending sends.
		if m.cancelFn != nil {
			m.cancelFn(context.Canceled)
		}
		// Wait for senders to release.
		m.respMu.Lock()
	}

    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          maybeDrainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    @GuardedBy("this")

      }
    }

    // reference queues, for garbage collection cleanup

    /** Cleanup collected entries when the lock is available. */
    void tryDrainReferenceQueues() {
      if (tryLock()) {
        try {
          drainReferenceQueues();
        } finally {
          unlock();
        }
      }
    }

    /**