t is unreachable.
 When a checked exception occurs, the asynchronous method implementation
 can flow the exception back to the resulting <code>CompletableFuture</code>
 either by raising a
 <a href="https://docs.oracle.com/en/java/javase/17/docs/api/java.base/java/util/concurrent/CompletionException.html" title="class or interface in java.util.concurrent" class="external-link"><code>CompletionException</code></a>
 with the original exception as the cause, or it can take the equivalent
 approach of exception