@Override
    public boolean isRunning() {
        return delegate.isRunning();
    }
A {@link SmartLifecycle} which retries to start the {@link Server} up to {@code maxAttempts}.
This is useful for testing that needs to bind a server to a random port number obtained in advance.
spring/boot3-autoconfigure/src/test/java/com/linecorp/armeria/spring/RetryableArmeriaServerGracefulShutdownLifecycle.java