content: /**
   * 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 backtype.storm.security.auth;
  
  import java.util.Map;
  import java.security.Principal;
  
  /**
   * Map a kerberos principal to a local user
   */
  public class KerberosPrincipalToLocal implements IPrincipalToLocal {
  
      /**
       * Invoked once immediately after construction
       * 
       * @param conf Storm configuration
       */
      public void prepare(Map storm_conf) {
      }
  
      /**
       * Convert a Principal to a local user name.
       * 
       * @param principal the principal to convert
       * @return The local user name.
       */
      public String toLocal(Principal principal) {
          // This technically does not conform with rfc1964, but should work so
          // long as you don't have any really odd names in your KDC.
          return principal == null ? null : principal.getName().split("[/@]")[0];
      }
  }
  