SUPPORTS_REMOVE,
  /**
   * Support for {@link ListIterator#add(Object)}; ignored for plain {@link Iterator}
   * implementations.
   */
  SUPPORTS_ADD,
  /**
   * Support for {@link ListIterator#set(Object)}; ignored for plain {@link Iterator}
   * implementations.
   */
  SUPPORTS_SET;

  /**
   * A set containing none of the optional features of the {@link Iterator} or {@link ListIterator}
   * interfaces.
   */

          .build();

  /**
   * type → implementation. Inherently mutable interfaces and abstract classes are mapped to their
   * default implementations and are "new"d upon get().
   */
  private static final ConcurrentMap<Class<?>, Class<?>> implementations = Maps.newConcurrentMap();

  private static <T> void setImplementation(Class<T> type, Class<? extends T> implementation) {

- **Switch Expressions** - Optimized implementations using switch expressions for better performance
- **Sequenced Collections** - Full support for Java 21 sequenced collections API with dedicated utility methods
- **Performance Focused** - Optimized implementations for better runtime performance with reduced memory allocation

 *
 * As policy, implementations of this interface are responsible for selecting which cookies to
 * accept and which to reject. A reasonable policy is to reject all cookies, though that may
 * interfere with session-based authentication schemes that require cookies.
 *
 * As persistence, implementations of this interface must also provide storage of cookies. Simple

 *   <li>{@link Tables}
 * </ul>
 *
 * <h2>Abstract implementations</h2>
 *
 * <ul>
 *   <li>{@link AbstractIterator}
 *   <li>{@link AbstractSequentialIterator}
 *   <li>{@link UnmodifiableIterator}
 *   <li>{@link UnmodifiableListIterator}
 * </ul>
 *
 * <h2>Forwarding collections</h2>
 *
 * We provide implementations of collections that forward all method calls to a delegate collection

 *   <li>{@link Tables}
 * </ul>
 *
 * <h2>Abstract implementations</h2>
 *
 * <ul>
 *   <li>{@link AbstractIterator}
 *   <li>{@link AbstractSequentialIterator}
 *   <li>{@link UnmodifiableIterator}
 *   <li>{@link UnmodifiableListIterator}
 * </ul>
 *
 * <h2>Forwarding collections</h2>
 *
 * We provide implementations of collections that forward all method calls to a delegate collection

 */
package org.codelibs.fess.app.service;

/**
 * Abstract base class for Fess application services.
 * This class provides common functionality and utilities for service implementations
 * throughout the Fess search application.
 */
public abstract class FessAppService {

    /**
     * Default constructor.
     */
    public FessAppService() {
        // Default constructor
    }

- OkHttp is a small and light dependency.  Don't introduce new dependencies or major new functionality.
- OkHttp targets the intersection of RFC correct *and* widely implemented.  Incorrect implementations that are very widely implemented e.g. a bug in Apache, Nginx, Google, Firefox should also be handled.

Before your code can be accepted into the project you must also sign the
[Individual Contributor License Agreement (CLA)][1].

 * [system DNS service][SYSTEM], which is the default. Some applications may provide their own
 * implementation to use a different DNS server, to prefer IPv6 addresses, to prefer IPv4 addresses,
 * or to force a specific known IP address.
 *
 * Implementations of this interface must be safe for concurrent use.
 */
fun interface Dns {
  /**

import org.lastaflute.web.response.ActionResponse;

/**
 * Interface for SSO (Single Sign-On) authenticator implementations.
 *
 * This interface defines the contract for SSO authentication providers that can be
 * integrated with Fess. Implementations handle specific SSO protocols like SAML,
 * OAuth, SPNEGO, or other authentication mechanisms. Each authenticator is responsible