import org.jspecify.annotations.Nullable;

/**
 * Executor ensuring that all Runnables submitted are executed in order, using the provided
 * Executor, and sequentially such that no two will ever be running at the same time.
 *
 * <p>Tasks submitted to {@link #execute(Runnable)} are executed in FIFO order.
 *
 * <p>The execution of tasks is done by one thread as long as there are tasks left in the queue.

          new ExpectedHashCode(
              new byte[] {
                (byte) 0xef, (byte) 0xcd, (byte) 0xab, (byte) 0x89,
                (byte) 0x67, (byte) 0x45, (byte) 0x23,
                    (byte) 0x01, // up to here, same bytes as above
                (byte) 0x01, (byte) 0x02, (byte) 0x03, (byte) 0x04,
                (byte) 0x05, (byte) 0x06, (byte) 0x07, (byte) 0x08
              },
              0x89abcdef,

        // Create new storage with same salt
        SecureCredentialStorage storage2 = new SecureCredentialStorage(masterPassword.clone(), salt);

        try {
            // Should be able to decrypt with same salt and password
            char[] decrypted = storage2.decryptCredentials(encrypted);
            assertArrayEquals(plaintext, decrypted, "Should decrypt correctly with same salt and password");

   * this {@code Joiner} otherwise.
   *
   * @since 20.0
   */
  public MapJoiner withKeyValueSeparator(char keyValueSeparator) {
    return withKeyValueSeparator(String.valueOf(keyValueSeparator));
  }

  /**
   * Returns a {@code MapJoiner} using the given key-value separator, and the same configuration as
   * this {@code Joiner} otherwise.

  }

  /**
   * Creates an ImmutableMap from the first n entries in entryArray. This implementation may replace
   * the entries in entryArray with its own entry objects (though they will have the same key/value
   * contents), and may take ownership of entryArray.
   */
  static <K, V> ImmutableMap<K, V> fromEntryArray(
      int n, @Nullable Entry<K, V>[] entryArray, boolean throwIfDuplicateKeys) {

    for (prefixFlag in prefixFlags) {
      FLAGS[prefixFlag or FLAG_PADDED] = FLAGS[prefixFlag] + "|PADDED"
    }

    FLAGS[FLAG_END_HEADERS] = "END_HEADERS" // Same as END_PUSH_PROMISE.
    FLAGS[FLAG_PRIORITY] = "PRIORITY" // Same as FLAG_COMPRESSED.
    FLAGS[FLAG_END_HEADERS or FLAG_PRIORITY] = "END_HEADERS|PRIORITY" // Only valid on HEADERS.

A single HTTP call may require follow-up requests to be made to handle authentication challenges, redirects, and HTTP-layer timeouts. In such cases multiple connections, requests, and responses may be attempted. Follow-ups are another reason a single call may trigger multiple events of the same type.

   *   {@code List<ListenableFuture<T>> futures = (List) executor.invokeAll(tasks);}
   * </pre>
   *
   * @return A list of {@code ListenableFuture} instances representing the tasks, in the same
   *     sequential order as produced by the iterator for the given task list, each of which has
   *     completed.
   * @throws RejectedExecutionException {@inheritDoc}
   * @throws NullPointerException if any task is null

But Facebook login doesn't support OpenID Connect. It has its own flavor of OAuth2.

### OpenID (not "OpenID Connect") { #openid-not-openid-connect }

There was also an "OpenID" specification. That tried to solve the same thing as **OpenID Connect**, but was not based on OAuth2.

So, it was a complete additional system.

It is not very popular or used nowadays.

## OpenAPI { #openapi }

   * Calling this method is as thread-safe as calling that method.
   *
   * @param collection a collection of {@code Character} objects
   * @return an array containing the same values as {@code collection}, in the same order, converted
   *     to primitives
   * @throws NullPointerException if {@code collection} or any of its elements is null
   */
  public static char[] toArray(Collection<Character> collection) {