001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018package org.apache.hadoop.hdfs.web.resources;
019
020import org.apache.hadoop.security.UserGroupInformation;
021
022/** Represents delegation token used for authentication. */
023public class DelegationParam extends StringParam {
024  /** Parameter name. */
025  public static final String NAME = "delegation";
026  /** Default parameter value. */
027  public static final String DEFAULT = "";
028
029  private static final Domain DOMAIN = new Domain(NAME, null);
030
031  /**
032   * Constructor.
033   * @param str a string representation of the parameter value.
034   */
035  public DelegationParam(final String str) {
036    super(DOMAIN, UserGroupInformation.isSecurityEnabled()
037        && str != null && !str.equals(DEFAULT)? str: null);
038  }
039
040  @Override
041  public String getName() {
042    return NAME;
043  }
044}