private static T assertTimeoutPreemptively()

in junit-jupiter-api/src/main/java/org/junit/jupiter/api/AssertTimeout.java [128:174]

43 lines of code
6 McCabe index (conditional complexity)


	private static <T> T assertTimeoutPreemptively(Duration timeout, ThrowingSupplier<T> supplier,
			Object messageOrSupplier) {

		AtomicReference<Thread> threadReference = new AtomicReference<>();
		ExecutorService executorService = Executors.newSingleThreadExecutor(new TimeoutThreadFactory());

		try {
			Future<T> future = executorService.submit(() -> {
				try {
					threadReference.set(Thread.currentThread());
					return supplier.get();
				}
				catch (Throwable throwable) {
					throw ExceptionUtils.throwAsUncheckedException(throwable);
				}
			});

			long timeoutInMillis = timeout.toMillis();
			try {
				return future.get(timeoutInMillis, TimeUnit.MILLISECONDS);
			}
			catch (TimeoutException ex) {
				String message = buildPrefix(nullSafeGet(messageOrSupplier)) + "execution timed out after "
						+ timeoutInMillis + " ms";

				Thread thread = threadReference.get();
				if (thread != null) {
					ExecutionTimeoutException exception = new ExecutionTimeoutException(
						"Execution timed out in thread " + thread.getName());
					exception.setStackTrace(thread.getStackTrace());
					throw new AssertionFailedError(message, exception);
				}
				else {
					throw new AssertionFailedError(message);
				}
			}
			catch (ExecutionException ex) {
				throw ExceptionUtils.throwAsUncheckedException(ex.getCause());
			}
			catch (Throwable ex) {
				throw ExceptionUtils.throwAsUncheckedException(ex);
			}
		}
		finally {
			executorService.shutdownNow();
		}
	}