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 com.alibaba.jstorm.schedule.default_assign.Selector;
  
  import java.util.ArrayList;
  import java.util.Comparator;
  import java.util.List;
  
  import com.alibaba.jstorm.schedule.default_assign.ResourceWorkerSlot;
  import com.alibaba.jstorm.schedule.default_assign.TaskAssignContext;
  
  public abstract class AbstractSelector implements Selector {
  
      protected final TaskAssignContext context;
  
      protected WorkerComparator workerComparator;
  
      protected WorkerComparator supervisorComparator;
  
      public AbstractSelector(TaskAssignContext context) {
          this.context = context;
      }
  
      protected List<ResourceWorkerSlot> selectWorker(List<ResourceWorkerSlot> list, Comparator<ResourceWorkerSlot> c) {
          List<ResourceWorkerSlot> result = new ArrayList<>();
          ResourceWorkerSlot best = null;
          for (ResourceWorkerSlot worker : list) {
              if (best == null) {
                  best = worker;
                  result.add(worker);
                  continue;
              }
              if (c.compare(best, worker) == 0) {
                  result.add(worker);
              } else if (c.compare(best, worker) > 0) {
                  best = worker;
                  result.clear();
                  result.add(best);
              }
          }
          return result;
      }
  
      @Override
      public List<ResourceWorkerSlot> select(List<ResourceWorkerSlot> result, String name) {
          if (result.size() == 1)
              return result;
          result = this.selectWorker(result, workerComparator.get(name));
          if (result.size() == 1)
              return result;
          return this.selectWorker(result, supervisorComparator.get(name));
      }
  
  }
  