Unchecked variant of {@link java.util.concurrent.ExecutionException}. As with
 * {@code ExecutionException}, the exception's {@linkplain #getCause() cause} comes from a failed
 * task, possibly run in another thread.
 *
 * <p>{@code UncheckedExecutionException} is intended as an alternative to
 * {@code ExecutionException} when the exception thrown by a task is an unchecked exception.
 * However, it may also wrap a checked exception in some cases.
 *
 * <p>When wrapping an {@code Error} from another thread, prefer {@link ExecutionError}. When
 * wrapping a checked exception, prefer {@code
 * ExecutionException}.
Unchecked variant of {@link java.util.concurrent.ExecutionException}. As with
 * {@code ExecutionException}, the exception's {@linkplain #getCause() cause} comes from a failed
 * task, possibly run in another thread.
 *
 * <p>{@code UncheckedExecutionException} is intended as an alternative to
 * {@code ExecutionException} when the exception thrown by a task is an unchecked exception.
 * However, it may also wrap a checked exception in some cases.
 *
 * <p>When wrapping an {@code Error} from another thread, prefer {@link ExecutionError}. When
 * wrapping a checked exception, prefer {@code
 * ExecutionException}. | UncheckedExecutionException.java