* your application's HTTP calls.
 *
 * All start/connect/acquire events will eventually receive a matching end/release event, either
 * successful (non-null parameters), or failed (non-null throwable). The first common parameters of
 * each event pair are used to link the event in case of concurrent or repeated events e.g.

    if (failedPing != -1) {
      failWebSocket(
        e =
          SocketTimeoutException(
            "sent ping but didn't receive pong within " +
              "${pingIntervalMillis}ms (after ${failedPing - 1} successful ping/pongs)",
          ),
        isWriter = true,
      )
      return
    }

    try {
      writer.writePing(ByteString.EMPTY)
    } catch (e: IOException) {

        added += q.drainTo(buffer, numElements - added);
        if (added < numElements) { // not enough elements immediately available; will have to poll
          E e; // written exactly once, by a successful (uninterrupted) invocation of #poll
          while (true) {
            try {
              e = q.poll(deadline - System.nanoTime(), NANOSECONDS);
              break;
            } catch (InterruptedException ex) {

        "version": "0.1.0"
    },
    "paths": {
        "/items/": {
            "get": {
                "responses": {
                    "200": {
                        "description": "Successful Response",
                        "content": {
                            "application/json": {



...
```

#### OpenAPIの目的

OpenAPIスキーマは、FastAPIに含まれている2つのインタラクティブなドキュメントシステムの動力源です。

     */
    public ApiResult(final ApiResponse response) {
        this.response = response;
    }

    /**
     * Represents the status of an API response.
     */
    public enum Status {
        /** Successful response status. */
        OK(0),
        /** Bad request status indicating client error. */
        BAD_REQUEST(1),
        /** System error status indicating server error. */
        SYSTEM_ERROR(2),

        added += q.drainTo(buffer, numElements - added);
        if (added < numElements) { // not enough elements immediately available; will have to poll
          E e; // written exactly once, by a successful (uninterrupted) invocation of #poll
          while (true) {
            try {
              e = q.poll(deadline - System.nanoTime(), NANOSECONDS);
              break;
            } catch (InterruptedException ex) {

// - freeze (freezes all incoming S3 API calls)
// - unfreeze (unfreezes previously frozen S3 API calls)
//
// This newer API now returns back status per remote peer and local regarding
// if a "restart/stop" was successful or not. Service signal now supports
// a dry-run that helps skip the nodes that may have hung drives. By default
// restart/stop will ignore the servers that are hung on drives. You can use

            log.debug("[{}] Success in HALF_OPEN state ({}/{})", name, successes, successThreshold);

            if (successes >= successThreshold) {
                log.info("[{}] Circuit breaker closing after {} successful attempts", name, successes);
                transitionTo(State.CLOSED);
            }
        } else if (currentState == State.CLOSED) {
            // Reset failure count on success in closed state

     *
     * @param hard if true, force immediate disconnection without waiting for pending requests
     * @param inUse whether the transport is currently in use
     * @return true if the disconnection was successful
     * @throws IOException if an I/O error occurs
     */
    protected abstract boolean doDisconnect(boolean hard, boolean inUse) throws IOException;

    /**
     * Connect the transport
     *

   * currently {@code expectedOldCount}. If {@code element} does not appear in the multiset exactly
   * {@code expectedOldCount} times, no changes will be made.
   *
   * @return {@code true} if the change was successful. This usually indicates that the multiset has
   *     been modified, but not always: in the case that {@code expectedOldCount == newCount}, the
   *     method will return {@code true} if the condition was met.