1 /**
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing, software
13 * distributed under the License is distributed on an "AS IS" BASIS,
14 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
15 * See the License for the specific language governing permissions and
16 * limitations under the License.
17 */
18
19 package org.apache.hadoop.hbase.regionserver;
20
21 import org.apache.hadoop.hbase.metrics.BaseSource;
22
23 /**
24 * This interface will be implemented by a MetricsSource that will export metrics from
25 * multiple users into the hadoop metrics system.
26 */
27 public interface MetricsUserAggregateSource extends BaseSource {
28
29 /**
30 * The name of the metrics
31 */
32 static final String METRICS_NAME = "Users";
33
34 /**
35 * The name of the metrics context that metrics will be under.
36 */
37 static final String METRICS_CONTEXT = "regionserver";
38
39 /**
40 * Description
41 */
42 static final String METRICS_DESCRIPTION = "Metrics about users connected to the regionserver";
43
44 /**
45 * The name of the metrics context that metrics will be under in jmx
46 */
47 static final String METRICS_JMX_CONTEXT = "RegionServer,sub=" + METRICS_NAME;
48
49 static final String NUM_USERS = "numUsers";
50 static final String NUMBER_OF_USERS_DESC = "Number of users in the metrics system";
51
52 /**
53 * Returns a MetricsUserSource if already exists, or creates and registers one for this user
54 * @param user the user name
55 * @return a metrics user source
56 */
57 MetricsUserSource getOrCreateMetricsUser(String user);
58
59 void deregister(MetricsUserSource toRemove);
60 }