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 backtype.storm.scheduler;
  
  import java.util.Collection;
  import java.util.Map;
  import java.util.Set;
  
  public interface INimbus {
      void prepare(Map stormConf, String schedulerLocalDir);
  
      /**
       * Returns all slots that are available for the next round of scheduling.
       * A slot is available for scheduling if it is free and can be assigned to, or if it
       * is used and can be reassigned.
       */
      Collection<WorkerSlot> allSlotsAvailableForScheduling(Collection<SupervisorDetails> existingSupervisors,
                                                            Topologies topologies,
                                                            Set<String> topologiesMissingAssignments);
  
      // this is called after the assignment is changed in ZK
      void assignSlots(Topologies topologies, Map<String, Collection<WorkerSlot>> newSlotsByTopologyId);
  
      // map from node id to supervisor details
      String getHostName(Map<String, SupervisorDetails> existingSupervisors, String nodeId);
  
      IScheduler getForcedScheduler();
  }
  