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.kafka.config;
  
  import org.apache.kafka.common.config.AbstractConfig;
  
  import java.util.Set;
  
  /**
   * An interface for Kafka broker configs that support dynamic reconfiguration.
   * <p>
   * Components that implement this interface can have their configurations updated
   * at runtime without requiring a broker restart.
   * <p>
   * The reconfiguration process follows three steps:
   * <ol>
   *   <li>Determining which configurations can be dynamically updated via {@link #reconfigurableConfigs()}</li>
   *   <li>Validating the new configuration before applying it via {@link #validateReconfiguration(AbstractConfig)}</li>
   *   <li>Applying the new configuration via {@link #reconfigure(AbstractConfig, AbstractConfig)}</li>
   * </ol>
   * <strong>Note: Since Kafka is eliminating Scala, developers should implement this interface instead of {@link kafka.server.BrokerReconfigurable}</strong>
   */
  public interface BrokerReconfigurable {
      /**
       * Returns the set of configuration keys that can be dynamically reconfigured.
       *
       * <p>
       * Only the configurations returned by this method will be considered for
       * dynamic updates by the broker.
       *
       * @return a set of configuration key names that can be dynamically updated
       */
      Set<String> reconfigurableConfigs();
  
      /**
       * Validates the new configuration before applying it.
       * <p>
       * This method should verify that the new configuration values are valid and
       * can be safely applied.
       *
       * @param newConfig the new configuration to validate
       */
      void validateReconfiguration(AbstractConfig newConfig);
  
      /**
       * Applies the new configuration.
       * <p>
       * This method is called after the new configuration has been validated.
       *
       * @param oldConfig the previous configuration
       * @param newConfig the new configuration to apply
       */
      void reconfigure(AbstractConfig oldConfig, AbstractConfig newConfig);
  }
  