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.streams.processor.internals.assignment;
  
  import org.apache.kafka.streams.processor.assignment.AssignmentConfigs;
  import org.apache.kafka.streams.processor.assignment.ProcessId;
  
  import java.util.Collections;
  import java.util.Map;
  
  import static org.apache.kafka.common.utils.Utils.mkEntry;
  import static org.apache.kafka.common.utils.Utils.mkMap;
  
  class StandbyTaskAssignorFactory {
      private StandbyTaskAssignorFactory() {}
  
      static StandbyTaskAssignor create(final AssignmentConfigs configs,
                                        final RackAwareTaskAssignor rackAwareTaskAssignor) {
          if (!configs.rackAwareAssignmentTags().isEmpty()) {
              return new ClientTagAwareStandbyTaskAssignor();
          } else if (rackAwareTaskAssignor != null && rackAwareTaskAssignor.validClientRack()) {
              // racksForProcess should be populated if rackAwareTaskAssignor isn't null
              final Map<ProcessId, String> racksForProcess = rackAwareTaskAssignor.racksForProcess();
              return new ClientTagAwareStandbyTaskAssignor(
                  (processId, clientState) -> mkMap(mkEntry("rack", racksForProcess.get(processId))),
                  assignmentConfigs -> Collections.singletonList("rack")
              );
          } else {
              return new DefaultStandbyTaskAssignor();
          }
      }
  }
  