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.cassandra.utils.logging;
  
  import java.util.Map;
  import java.util.Optional;
  
  import ch.qos.logback.classic.Logger;
  import ch.qos.logback.core.Appender;
  
  /**
   * Common abstraction of functionality which can be implemented for different logging backend implementations (slf4j bindings).
   * Concrete implementations are dynamically loaded and instantiated by {@link LoggingSupportFactory#getLoggingSupport()}.
   */
  public interface LoggingSupport
  {
      /**
       * Hook used to execute logging implementation specific customization at Cassandra startup time.
       */
      default void onStartup() {}
  
      /**
       * Hook used to execute logging implementation specific customization at Cassandra shutdown time.
       */
      default void onShutdown() {}
  
      /**
       * Changes the given logger to the given log level.
       *
       * @param classQualifier the class qualifier or logger name
       * @param rawLevel the string representation of a log level
       * @throws Exception an exception which may occur while changing the given logger to the given log level.
       */
      void setLoggingLevel(String classQualifier, String rawLevel) throws Exception;
  
      /**
       * @return a map of logger names and their associated log level as string representations.
       */
      Map<String, String> getLoggingLevels();
  
      default <T extends Appender<?>> Optional<T> getAppender(Class<T> appenderClass, String appenderName)
      {
          return Optional.empty();
      }
  
      default Optional<Logger> getLogger(String loggerName)
      {
          return Optional.empty();
      }
  }
  