content: /*
   * Copyright 2022 The FeatHub Authors
   *
   * Licensed 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
   *
   *     https://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.feathub.flink.connectors.prometheus;
  
  import io.prometheus.client.CollectorRegistry;
  import io.prometheus.client.Gauge;
  
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  
  /** The DoubleListMetricUpdater updates Prometheus gauge metrics with a list of double values. */
  public class DoubleListMetricUpdater extends AbstractListMetricUpdater<Double> {
  
      private final List<Gauge.Child> children;
  
      public DoubleListMetricUpdater(
              String name, List<Map<String, String>> labelLists, CollectorRegistry registry) {
          super(name, labelLists, registry);
  
          this.children = new ArrayList<>();
          for (Map<String, String> labelsSet : labelLists) {
              children.add(collector.labels(labelsSet.values().toArray(new String[0])));
          }
      }
  
      @Override
      public void update(List<Double> values) {
          if (values.size() != children.size()) {
              throw new RuntimeException(
                      "List metric size must be the same as the number of label lists.");
          }
          for (int i = 0; i < values.size(); ++i) {
              children.get(i).set(values.get(i));
          }
      }
  }
  