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 io.prometheus.client.SimpleCollector;
  
  import java.util.Map;
  
  /** The SimpleMetricUpdater updates a Prometheus gauge metric with a Double value. */
  public class SimpleMetricUpdater implements MetricUpdater<Double> {
  
      private final Gauge.Child child;
  
      public SimpleMetricUpdater(
              String name, Map<String, String> labels, CollectorRegistry registry) {
          SimpleCollector<Gauge.Child> collector =
                  Gauge.build()
                          .name(name)
                          .help(name)
                          .labelNames(labels.keySet().toArray(new String[0]))
                          .register(registry);
          child = collector.labels(labels.values().toArray(new String[0]));
      }
  
      @Override
      public void update(Double value) {
          child.set(value);
      }
  }
  