content: /*
   * The Alluxio Open Foundation licenses this work under the Apache License, version 2.0
   * (the "License"). You may not use this work except in compliance with the License, which is
   * available at www.apache.org/licenses/LICENSE-2.0
   *
   * This software is distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
   * either express or implied, as more fully set forth in the License.
   *
   * See the NOTICE file distributed with this work for information regarding copyright ownership.
   */
  
  package alluxio.conf.path;
  
  import alluxio.AlluxioURI;
  import alluxio.conf.AlluxioConfiguration;
  import alluxio.conf.PropertyKey;
  
  import java.util.Map;
  import java.util.Optional;
  import java.util.Set;
  
  /**
   * Path level configuration.
   *
   * An {@link AlluxioConfiguration} is set for each path pattern. This class matches an Alluxio
   * path against the patterns, then from the configurations of the matched patterns, it chooses the
   * configuration that contains the specified property key and belongs to the best matched pattern.
   *
   * Different implementations have different definitions of the best match.
   */
  public interface PathConfiguration {
    /**
     * @param path the Alluxio path
     * @param key the property key
     * @return the chosen configuration matching the path and containing the key
     */
    Optional<AlluxioConfiguration> getConfiguration(AlluxioURI path, PropertyKey key);
  
    /**
     * @param path the Alluxio path
     * @return all property keys in the path level configuration that is applicable to path
     */
    Set<PropertyKey> getPropertyKeys(AlluxioURI path);
  
    /**
     * Factory method to create an implementation of {@link PathConfiguration}.
     *
     * @param pathConf the map from paths to path level configurations
     * @return the implementation of {@link PathConfiguration}
     */
    static PathConfiguration create(Map<String, AlluxioConfiguration> pathConf) {
      return new PrefixPathConfiguration(pathConf);
    }
  }
  