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 com.datastax.oss.driver.internal.core.metrics;
  
  import edu.umd.cs.findbugs.annotations.NonNull;
  import java.util.Map;
  
  /**
   * The identifier of a metric.
   *
   * <p>The driver will use the reported name and tags to register the described metric against the
   * current metric registry.
   *
   * <p>A metric identifier is unique, that is, the combination of its name and its tags is expected
   * to be unique for a given metric registry.
   */
  public interface MetricId {
  
    /**
     * Returns this metric name.
     *
     * <p>Metric names can be any non-empty string, but it is recommended to create metric names that
     * have path-like structures separated by a dot, e.g. {@code path.to.my.custom.metric}. Driver
     * built-in implementations of this interface abide by this rule.
     *
     * @return The metric name; cannot be empty nor null.
     */
    @NonNull
    String getName();
  
    /** @return The metric tags, or empty if no tag is defined; cannot be null. */
    @NonNull
    Map<String, String> getTags();
  }
  