content: /*
   * Copyright (c) 2003, 2013, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
   * particular file as subject to the "Classpath" exception as provided
   * by Oracle in the LICENSE file that accompanied this code.
   *
   * This code is distributed in the hope that it will be useful, but WITHOUT
   * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
   * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
   * version 2 for more details (a copy is included in the LICENSE file that
   * accompanied this code).
   *
   * You should have received a copy of the GNU General Public License version
   * 2 along with this work; if not, write to the Free Software Foundation,
   * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
   *
   * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
   * or visit www.oracle.com if you need additional information or have any
   * questions.
   */
  
  package java.net;
  
  import java.util.Map;
  import java.util.List;
  import java.io.IOException;
  import sun.security.util.SecurityConstants;
  
  /**
   * A CookieHandler object provides a callback mechanism to hook up a
   * HTTP state management policy implementation into the HTTP protocol
   * handler. The HTTP state management mechanism specifies a way to
   * create a stateful session with HTTP requests and responses.
   *
   * <p>A system-wide CookieHandler that to used by the HTTP protocol
   * handler can be registered by doing a
   * CookieHandler.setDefault(CookieHandler). The currently registered
   * CookieHandler can be retrieved by calling
   * CookieHandler.getDefault().
   *
   * For more information on HTTP state management, see <a
   * href="http://www.ietf.org/rfc/rfc2965.txt"><i>RFC&nbsp;2965: HTTP
   * State Management Mechanism</i></a>
   *
   * @author Yingxian Wang
   * @since 1.5
   */
  public abstract class CookieHandler {
      /**
       * The system-wide cookie handler that will apply cookies to the
       * request headers and manage cookies from the response headers.
       *
       * @see setDefault(CookieHandler)
       * @see getDefault()
       */
      private static CookieHandler cookieHandler;
  
      /**
       * Gets the system-wide cookie handler.
       *
       * @return the system-wide cookie handler; A null return means
       *        there is no system-wide cookie handler currently set.
       * @throws SecurityException
       *       If a security manager has been installed and it denies
       * {@link NetPermission}{@code ("getCookieHandler")}
       * @see #setDefault(CookieHandler)
       */
      public synchronized static CookieHandler getDefault() {
          SecurityManager sm = System.getSecurityManager();
          if (sm != null) {
              sm.checkPermission(SecurityConstants.GET_COOKIEHANDLER_PERMISSION);
          }
          return cookieHandler;
      }
  
      /**
       * Sets (or unsets) the system-wide cookie handler.
       *
       * Note: non-standard http protocol handlers may ignore this setting.
       *
       * @param cHandler The HTTP cookie handler, or
       *       {@code null} to unset.
       * @throws SecurityException
       *       If a security manager has been installed and it denies
       * {@link NetPermission}{@code ("setCookieHandler")}
       * @see #getDefault()
       */
      public synchronized static void setDefault(CookieHandler cHandler) {
          SecurityManager sm = System.getSecurityManager();
          if (sm != null) {
              sm.checkPermission(SecurityConstants.SET_COOKIEHANDLER_PERMISSION);
          }
          cookieHandler = cHandler;
      }
  
      /**
       * Gets all the applicable cookies from a cookie cache for the
       * specified uri in the request header.
       *
       * <P>The {@code URI} passed as an argument specifies the intended use for
       * the cookies. In particular the scheme should reflect whether the cookies
       * will be sent over http, https or used in another context like javascript.
       * The host part should reflect either the destination of the cookies or
       * their origin in the case of javascript.</P>
       * <P>It is up to the implementation to take into account the {@code URI} and
       * the cookies attributes and security settings to determine which ones
       * should be returned.</P>
       *
       * <P>HTTP protocol implementers should make sure that this method is
       * called after all request headers related to choosing cookies
       * are added, and before the request is sent.</P>
       *
       * @param uri a {@code URI} representing the intended use for the
       *            cookies
       * @param requestHeaders - a Map from request header
       *            field names to lists of field values representing
       *            the current request headers
       * @return an immutable map from state management headers, with
       *            field names "Cookie" or "Cookie2" to a list of
       *            cookies containing state information
       *
       * @throws IOException if an I/O error occurs
       * @throws IllegalArgumentException if either argument is null
       * @see #put(URI, Map)
       */
      public abstract Map<String, List<String>>
          get(URI uri, Map<String, List<String>> requestHeaders)
          throws IOException;
  
      /**
       * Sets all the applicable cookies, examples are response header
       * fields that are named Set-Cookie2, present in the response
       * headers into a cookie cache.
       *
       * @param uri a {@code URI} where the cookies come from
       * @param responseHeaders an immutable map from field names to
       *            lists of field values representing the response
       *            header fields returned
       * @throws  IOException if an I/O error occurs
       * @throws  IllegalArgumentException if either argument is null
       * @see #get(URI, Map)
       */
      public abstract void
          put(URI uri, Map<String, List<String>> responseHeaders)
          throws IOException;
  }
  