* Initializes the service with dependency injection.
     */
    public RequestHeaderService() {
        // Default constructor
    }

    /**
     * Retrieves a paginated list of request headers based on the provided pager criteria.
     *
     * @param requestHeaderPager the pager containing pagination and search criteria
     * @return a list of request headers matching the specified criteria
     */

   *   <li>Unusual environments like GWT may have their own special handling of system properties.
   * </ul>
   *
   * <p>Note that {@code StandardSystemProperty} does not provide constants for more recently added
   * properties, including:
   *
   * <ul>
   *   <li>{@code java.vendor.version} (added in Java 11, listed as optional as of Java 13)

@GwtCompatible
abstract class AbstractListMultimap<K extends @Nullable Object, V extends @Nullable Object>
    extends AbstractMapBasedMultimap<K, V> implements ListMultimap<K, V> {
  /**
   * Creates a new multimap that uses the provided map.
   *
   * @param map place to store the mapping from each key to its corresponding values
   */
  protected AbstractListMultimap(Map<K, Collection<V>> map) {
    super(map);
  }

  @Override

 * change the behavior of {@link #equals}, which can lead to unexpected behavior. In this case, you
 * should override {@code equals} as well, either providing your own implementation, or delegating
 * to the provided {@code standardEquals} method.
 *
 * <p>Each of the {@code standard} methods, where appropriate, use {@link Objects#equals} to test
 * equality for both keys and values. This may not be the desired behavior for map implementations

import java.net.URLStreamHandler;
import java.net.URLStreamHandlerFactory;
import java.util.HashMap;
import java.util.Map;
import java.util.StringTokenizer;

/**
 * A <code>URLStreamHandler</code> used to provide NTLM authentication
 * capabilities to the default HTTP handler.  This acts as a wrapper,
 * handling authentication and passing control to the underlying
 * stream handler.
 */
public class Handler extends URLStreamHandler {

    }

    /**
     * Retrieves a paginated list of stemmer override items from the specified dictionary.
     *
     * This method fetches stemmer override entries with pagination support, updating
     * the provided pager with the current page state and navigation information.
     *
     * @param dictId The ID of the stemmer override dictionary to query
     * @param stemmerOvberridePager The pager object for pagination control and state

    /**
     * Fess configuration settings.
     */
    @Resource
    protected FessConfig fessConfig;

    /**
     * Gets a paginated list of web configurations based on the provided pager.
     *
     * @param webConfigPager The pager containing pagination and search criteria
     * @return List of web configuration objects
     */

  /**
   * An alternate form of {@code put} that silently removes any existing entry with the value {@code
   * value} before proceeding with the {@link #put} operation. If the bimap previously contained the
   * provided key-value mapping, this method has no effect.
   *
   * <p>Note that a successful call to this method could cause the size of the bimap to increase by
   * one, stay the same, or even decrease by one.
   *

            // each pair is [dosCode, ntStatus]
            if (pair != null && pair.length == 2 && pair[0] == dosCode) {
                return pair[1];
            }
        }
        return -1;
    }

    // Provide a handful of representative mappings present in the table.
    static Stream<Arguments> knownMappings() {

FastAPI provides several tools for each of these security schemes in the `fastapi.security` module that simplify using these security mechanisms.

In the next chapters you will see how to add security to your API using those tools provided by **FastAPI**.