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.concurrent;
  
  import org.apache.cassandra.utils.Shared;
  
  import static org.apache.cassandra.utils.Shared.Scope.SIMULATION;
  
  @Shared(scope = SIMULATION)
  public interface ResizableThreadPool
  {
      /**
       * Returns core pool size of thread pool, the minimum
       * number of workers (where that makes sense for a thread pool,
       * SEPExecutor does not have a minimum size).
       */
      public int getCorePoolSize();
  
      /**
       * Allows user to resize minimum size of the thread pool.
       */
      public void setCorePoolSize(int newCorePoolSize);
  
      /**
       * Returns maximum pool size of thread pool.
       */
      public int getMaximumPoolSize();
  
      /**
       * Allows user to resize maximum size of the thread pool.
       */
      public void setMaximumPoolSize(int newMaximumPoolSize);
  
      /**
       * Returns the approximate number of threads that are actively
       * executing tasks.
       *
       * @return the number of threads
       */
      int getActiveTaskCount();
  
      /**
       * Returns the approximate total number of tasks that have
       * completed execution. Because the states of tasks and threads
       * may change dynamically during computation, the returned value
       * is only an approximation, but one that does not ever decrease
       * across successive calls.
       *
       * @return the number of tasks
       */
      long getCompletedTaskCount();
  
      /**
       * Returns the approximate total of tasks waiting to be executed.
       * Because the states of tasks and threads may change dynamically
       * during computation, the returned value is only an approximation.
       *
       * @return the number of tasks
       */
      int getPendingTaskCount();
  
      default int getMaxTasksQueued()
      {
          return -1;
      }
  
      default long oldestTaskQueueTime()
      {
          return 0;
      }
  }
  