# Lifespan Events { #lifespan-events }

You can define logic (code) that should be executed before the application **starts up**. This means that this code will be executed **once**, **before** the application **starts receiving requests**.

The same way, you can define logic (code) that should be executed when the application is **shutting down**. In this case, this code will be executed **once**, **after** having handled possibly **many requests**.

1. The client looks for a compatible idle daemon. If there isn't one, it starts a new daemon.
2. The client connects to the idle daemon and sends it a request to do some work. If the daemon is no longer running, the client starts again.
3. If the daemon is not able to run the request, for example it is already running a request or is shutting down, it rejects the request. The client starts again.

 *
 * <p>This implementation is based on the <a
 * href="http://portal.acm.org/citation.cfm?id=6621">min-max heap</a> developed by Atkinson, et al.
 * Unlike many other double-ended priority queues, it stores elements in a single array, as compact
 * as the traditional heap data structure used in {@link PriorityQueue}.
 *
 * <p>This class is not thread-safe, and does not accept null elements.
 *
 * <p><i>Performance notes:</i>

            ListTestSuiteBuilder.using(new ShortsAsListTailSubListGenerator())
                .named("Shorts.asList, tail subList"),
            ListTestSuiteBuilder.using(new ShortsAsListMiddleSubListGenerator())
                .named("Shorts.asList, middle subList"));

    TestSuite suite = new TestSuite();
    for (ListTestSuiteBuilder<Short> builder : builders) {
      suite.addTest(
          builder

            ListTestSuiteBuilder.using(new ShortsAsListTailSubListGenerator())
                .named("Shorts.asList, tail subList"),
            ListTestSuiteBuilder.using(new ShortsAsListMiddleSubListGenerator())
                .named("Shorts.asList, middle subList"));

    TestSuite suite = new TestSuite();
    for (ListTestSuiteBuilder<Short> builder : builders) {
      suite.addTest(
          builder

        assertArgumentNotNull("props", props);
        assertArgumentNotNull("writer", writer);

        try {
            props.store(writer, comments);
        } catch (final IOException e) {
            throw new IORuntimeException(e);
        }
    }

    /**
     * Stores the {@link Properties} to a file with the specified encoding (wraps exception handling).
     *
     * @param props

            if (url != null) {
                return url;
            }
            return id;
        }
    }

    /**
     * Statistics data object that stores timestamped events and maintains reference counting.
     * Extends LinkedHashMap to store event names mapped to their timestamps.
     * Includes reference counting for multi-threaded access tracking.
     */

      extends AbstractBiMap<K, V> {
    Inverse(Map<K, V> backward, AbstractBiMap<V, K> forward) {
      super(backward, forward);
    }

    /*
     * Serialization stores the forward bimap, the inverse of this inverse.
     * Deserialization calls inverse() on the forward bimap and returns that
     * inverse.
     *
     * If a bimap and its inverse are serialized together, the deserialized

* (Optionally) use `PATCH` instead of `PUT`.
* Retrieve the stored data.
* Put that data in a Pydantic model.
* Generate a `dict` without default values from the input model (using `exclude_unset`).
    * This way you can update only the values actually set by the user, instead of overriding values already stored with default values in your model.

      field = value
      delegate.dispatcher = value.wrap()
    }

  val port: Int
    get() {
      before() // This implicitly starts the delegate.
      return delegate.port
    }

  val hostName: String
    get() {
      before() // This implicitly starts the delegate.
      return delegate.hostName
    }

  var protocolNegotiationEnabled: Boolean by delegate::protocolNegotiationEnabled