001/**
002 * Licensed to the Apache Software Foundation (ASF) under one
003 * or more contributor license agreements.  See the NOTICE file
004 * distributed with this work for additional information
005 * regarding copyright ownership.  The ASF licenses this file
006 * to you under the Apache License, Version 2.0 (the
007 * "License"); you may not use this file except in compliance
008 * with the License.  You may obtain a copy of the License at
009 *
010 *     http://www.apache.org/licenses/LICENSE-2.0
011 *
012 * Unless required by applicable law or agreed to in writing, software
013 * distributed under the License is distributed on an "AS IS" BASIS,
014 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015 * See the License for the specific language governing permissions and
016 * limitations under the License.
017 */
018
019package org.apache.hadoop.hbase.regionserver;
020
021import java.util.Map;
022
023import org.apache.hadoop.hbase.metrics.BaseSource;
024import org.apache.yetus.audience.InterfaceAudience;
025
026/**
027* This interface will be implemented by a MetricsSource that will export metrics from
028* multiple users into the hadoop metrics system.
029*/
030@InterfaceAudience.Private
031public interface MetricsUserAggregateSource extends BaseSource {
032
033  /**
034   * The name of the metrics
035   */
036  static final String METRICS_NAME = "Users";
037
038  /**
039   * The name of the metrics context that metrics will be under.
040   */
041  static final String METRICS_CONTEXT = "regionserver";
042
043  /**
044   * Description
045   */
046  static final String METRICS_DESCRIPTION = "Metrics about users connected to the regionserver";
047
048  /**
049   * The name of the metrics context that metrics will be under in jmx
050   */
051  static final String METRICS_JMX_CONTEXT = "RegionServer,sub=" + METRICS_NAME;
052
053  static final String NUM_USERS = "numUsers";
054  static final String NUMBER_OF_USERS_DESC = "Number of users in the metrics system";
055
056  /**
057   * Returns a MetricsUserSource if already exists, or creates and registers one for this user
058   * @param user the user name
059   * @return a metrics user source
060   */
061  MetricsUserSource getOrCreateMetricsUser(String user);
062
063  void deregister(MetricsUserSource toRemove);
064
065  Map<String, MetricsUserSource> getUserSources();
066}