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.server.metrics;
  
  import com.yammer.metrics.core.Metric;
  import com.yammer.metrics.core.MetricName;
  import com.yammer.metrics.core.MetricsRegistry;
  import com.yammer.metrics.reporting.JmxReporter;
  
  import java.util.function.Predicate;
  
  public class FilteringJmxReporter extends JmxReporter {
  
      private volatile Predicate<MetricName> metricPredicate;
  
      public FilteringJmxReporter(MetricsRegistry registry, Predicate<MetricName> metricPredicate) {
          super(registry);
          this.metricPredicate = metricPredicate;
      }
  
      @Override
      public void onMetricAdded(MetricName name, Metric metric) {
          if (metricPredicate.test(name)) {
              super.onMetricAdded(name, metric);
          }
      }
  
      public void updatePredicate(Predicate<MetricName> predicate) {
          this.metricPredicate = predicate;
          // re-register metrics on update
          getMetricsRegistry()
              .allMetrics()
              .forEach((name, metric) -> {
                  if (metricPredicate.test(name)) {
                      super.onMetricAdded(name, metric);
                  } else {
                      super.onMetricRemoved(name);
                  }
              }
              );
      }
  }
  