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 org.apache.arrow.flight.auth2;
  
  import org.apache.arrow.flight.CallHeaders;
  
  /** Utility class for completing the auth process. */
  public final class AuthUtilities {
    private AuthUtilities() {}
  
    /**
     * Helper method for retrieving a value from the Authorization header.
     *
     * @param headers The headers to inspect.
     * @param valuePrefix The prefix within the value portion of the header to extract away.
     * @return The header value.
     */
    public static String getValueFromAuthHeader(CallHeaders headers, String valuePrefix) {
      final String authHeaderValue = headers.get(Auth2Constants.AUTHORIZATION_HEADER);
      if (authHeaderValue != null) {
        if (authHeaderValue.regionMatches(true, 0, valuePrefix, 0, valuePrefix.length())) {
          return authHeaderValue.substring(valuePrefix.length());
        }
      }
      return null;
    }
  }
  