code: /**
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements. See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership. The ASF licenses this file
   * to you under the Apache License, Version 2.0 (the
   * "License"); you may not use this file except in compliance
   * with the License. You may obtain a copy of the License at
   *
   * http://www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing,
   * software distributed under the License is distributed on an
   * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
   * KIND, either express or implied. See the License for the
   * specific language governing permissions and limitations
   * under the License.
   */
  
  package org.apache.cxf.ws.security.tokenstore;
  
  import java.util.Collection;
  
  /**
   * This interface defines a caching mechanism for security tokens. It is up to the underlying implementation
   * to handle token expiration (e.g. by querying the SecurityToken's expires date).
   */
  public interface TokenStore {
      
      /**
       * Add the given token to the cache. The SecurityTokens getId() identifier will be used to
       * key it in the cache.
       * @param token The token to be added
       */
      void add(SecurityToken token);
      
      /**
       * Add the given token to the cache under the given identifier
       * @param identifier The identifier to use to key the SecurityToken in the cache
       * @param token The token to be added
       */
      void add(String identifier, SecurityToken token);
      
      /**
       * Remove an existing token by its identifier
       */
      void remove(String identifier);
      
      /**
       * Return the list of all valid token identifiers.
       * @return As array of (valid) token identifiers
       */
      Collection<String> getTokenIdentifiers();
      
      /**
       * Return the list of expired tokens.
       * @return An array of expired <code>Tokens</code>
       */
      Collection<SecurityToken> getExpiredTokens();
      
      /**
       * Returns the <code>Token</code> of the given identifier
       * @param identifier
       * @return The requested <code>Token</code> identified by the given identifier
       */
      SecurityToken getToken(String identifier);
  
  }
  