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.image.node;
  
  import org.apache.kafka.image.FeaturesImage;
  
  import java.util.ArrayList;
  import java.util.Collection;
  
  
  public class FeaturesImageNode implements MetadataNode {
      /**
       * The name of this node.
       */
      public static final String NAME = "features";
  
      /**
       * The name of the metadata version child node.
       */
      public static final String METADATA_VERSION = "metadataVersion";
  
      /**
       * The name of the zk migration state child node.
       */
      public static final String ZK_MIGRATION_STATE = "zkMigrationState";
  
      /**
       * The prefix to put before finalized feature children.
       */
      public static final String FINALIZED_PREFIX = "finalized_";
  
      /**
       * The features image.
       */
      private final FeaturesImage image;
  
      public FeaturesImageNode(FeaturesImage image) {
          this.image = image;
      }
  
      @Override
      public Collection<String> childNames() {
          ArrayList<String> childNames = new ArrayList<>();
          childNames.add(METADATA_VERSION);
          childNames.add(ZK_MIGRATION_STATE);
          for (String featureName : image.finalizedVersions().keySet()) {
              childNames.add(FINALIZED_PREFIX + featureName);
          }
          return childNames;
      }
  
      @Override
      public MetadataNode child(String name) {
          if (name.equals(METADATA_VERSION)) {
              return new MetadataLeafNode(image.metadataVersion().toString());
          } else if (name.startsWith(FINALIZED_PREFIX)) {
              String key = name.substring(FINALIZED_PREFIX.length());
              return new MetadataLeafNode(
                      image.finalizedVersions().getOrDefault(key, (short) 0).toString());
          } else {
              return null;
          }
      }
  }
  