* That may happen later by the connection pool thread.
   */
  fun cancel()

  /**
   * Carries an exchange. This is usually a connection, but it could also be a connect plan for
   * CONNECT tunnels. Note that CONNECT tunnels are significantly less capable than connections.
   */
  interface Carrier {
    val route: Route

    fun trackFailure(
      call: RealCall,

     * execute Queue#drainTo is not added *on top* of waiting for the timeout (which could make
     * the timeout arbitrarily inaccurate, given a queue that is slow to drain).
     */
    long deadline = System.nanoTime() + unit.toNanos(timeout);
    int added = 0;
    while (added < numElements) {
      // we could rely solely on #poll, but #drainTo might be more efficient when there are multiple

        if (NAME.equals(config)) {
            try {
                return prompter.promptForPassword("Enter the master password: ");
            } catch (PrompterException e) {
                throw new SecDispatcherException("Could not collect the password", e);
            }
        }
        return null;
    }

    @Override
    public SecDispatcher.ValidationResponse validateConfiguration(String config) {
        if (NAME.equals(config)) {

        for (RepositoryEvent evt : event.getAllValues()) {
            if (EventType.ARTIFACT_DESCRIPTOR_MISSING.equals(evt.getType())) {
                assertEquals(
                        "Could not find artifact org.apache.maven.its:dep-mng5459:pom:0.4.0-20130404.090532-2 in repo ("
                                + newTestRepository().getUrl() + ")",
                        evt.getException().getMessage());

It might also help avoid confusion for new developers that see an unused parameter in your code and could think it's unnecessary.

///

/// info

In this example we use invented custom headers `X-Key` and `X-Token`.

But in real cases, when implementing security, you would get more benefits from using the integrated [Security utilities (the next chapter)](../security/index.md){.internal-link target=_blank}.

 * such custom interfaces directly; they are implemented only in subclasses. Therefore, forwarding
 * {@code equals} would break symmetry, as the forwarding object might consider itself equal to the
 * object being tested, but the reverse could not be true. This behavior is consistent with the
 * JDK's collection wrappers, such as {@link java.util.Collections#unmodifiableCollection}. Use an

public class ExecutionError extends Error {
  /*
   * Ideally, this class would have exposed only constructors that require a non-null cause. See
   * https://github.com/jspecify/jspecify-reference-checker/blob/61aafa4ae52594830cfc2d61c8b113009dbdb045/src/main/java/com/google/jspecify/nullness/NullSpecTransfer.java#L789
   * and https://github.com/jspecify/jspecify/issues/490.
   *

         * ended up with a magic value that is not compatible with the type of the configured mojo parameter (a string
         * could still be converted by the configurator so we leave those alone). If so, back off to evaluating the
         * expression from properties only.
         */

        return pluginDescriptor;
    }

    private static String toMessage(String goal, PluginDescriptor pluginDescriptor) {
        StringBuilder buffer = new StringBuilder(256);

        buffer.append("Could not find goal '").append(goal).append('\'');

        if (pluginDescriptor != null) {
            buffer.append(" in plugin ").append(pluginDescriptor.getId());

            buffer.append(" among available goals ");

* Import `StaticFiles`.
* "Mount" a `StaticFiles()` instance in a specific path.

{* ../../docs_src/static_files/tutorial001_py39.py hl[2,6] *}

/// note | Technical Details

You could also use `from starlette.staticfiles import StaticFiles`.

**FastAPI** provides the same `starlette.staticfiles` as `fastapi.staticfiles` just as a convenience for you, the developer. But it actually comes directly from Starlette.