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 */
018package org.apache.hadoop.hbase.regionserver;
019
020import org.apache.hadoop.hbase.metrics.BaseSource;
021import org.apache.yetus.audience.InterfaceAudience;
022
023/**
024 * This interface will be implemented by a MetricsSource that will export metrics from multiple
025 * regions into the hadoop metrics system.
026 */
027@InterfaceAudience.Private
028public interface MetricsRegionAggregateSource extends BaseSource {
029
030  /**
031   * The name of the metrics
032   */
033  String METRICS_NAME = "Regions";
034
035  /**
036   * The name of the metrics context that metrics will be under.
037   */
038  String METRICS_CONTEXT = "regionserver";
039
040  /**
041   * Description
042   */
043  String METRICS_DESCRIPTION = "Metrics about HBase RegionServer regions and tables";
044
045  /**
046   * The name of the metrics context that metrics will be under in jmx
047   */
048  String METRICS_JMX_CONTEXT = "RegionServer,sub=" + METRICS_NAME;
049
050  String NUMBER_OF_REGIONS_DESC = "Number of regions in the metrics system";
051
052  /**
053   * Register a MetricsRegionSource as being open.
054   * @param source the source for the region being opened.
055   */
056  void register(MetricsRegionSource source);
057
058  /**
059   * Remove a region's source. This is called when a region is closed.
060   * @param source The region to remove.
061   */
062  void deregister(MetricsRegionSource source);
063}