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;
  
  import org.apache.kafka.common.metadata.ClientQuotaRecord;
  
  import java.util.HashMap;
  import java.util.Map;
  import java.util.OptionalDouble;
  
  import static java.util.Map.Entry;
  
  
  public final class ClientQuotaDelta {
      private final ClientQuotaImage image;
      private final Map<String, OptionalDouble> changes = new HashMap<>();
  
      public ClientQuotaDelta(ClientQuotaImage image) {
          this.image = image;
      }
  
      public Map<String, OptionalDouble> changes() {
          return changes;
      }
  
      public void finishSnapshot() {
          for (String key : image.quotas().keySet()) {
              if (!changes.containsKey(key)) {
                  // If a quota from the image did not appear in the snapshot, mark it as removed.
                  changes.put(key, OptionalDouble.empty());
              }
          }
      }
  
      public void replay(ClientQuotaRecord record) {
          if (record.remove()) {
              changes.put(record.key(), OptionalDouble.empty());
          } else {
              changes.put(record.key(), OptionalDouble.of(record.value()));
          }
      }
  
      public ClientQuotaImage apply() {
          Map<String, Double> newQuotas = new HashMap<>(image.quotas().size());
          for (Entry<String, Double> entry : image.quotas().entrySet()) {
              OptionalDouble change = changes.get(entry.getKey());
              if (change == null) {
                  newQuotas.put(entry.getKey(), entry.getValue());
              } else if (change.isPresent()) {
                  newQuotas.put(entry.getKey(), change.getAsDouble());
              }
          }
          for (Entry<String, OptionalDouble> entry : changes.entrySet()) {
              if (!newQuotas.containsKey(entry.getKey())) {
                  if (entry.getValue().isPresent()) {
                      newQuotas.put(entry.getKey(), entry.getValue().getAsDouble());
                  }
              }
          }
          return new ClientQuotaImage(newQuotas);
      }
  }
  