001/*
002 *
003 * Licensed to the Apache Software Foundation (ASF) under one
004 * or more contributor license agreements.  See the NOTICE file
005 * distributed with this work for additional information
006 * regarding copyright ownership.  The ASF licenses this file
007 * to you under the Apache License, Version 2.0 (the
008 * "License"); you may not use this file except in compliance
009 * with the License.  You may obtain a copy of the License at
010 *
011 * http://www.apache.org/licenses/LICENSE-2.0
012 *
013 * Unless required by applicable law or agreed to in writing, software
014 * distributed under the License is distributed on an "AS IS" BASIS,
015 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
016 * See the License for the specific language governing permissions and
017 * limitations under the License.
018 */
019
020package org.apache.hadoop.hbase.coprocessor;
021
022import org.apache.yetus.audience.InterfaceAudience;
023import org.apache.yetus.audience.InterfaceStability;
024import org.apache.hadoop.hbase.CoprocessorEnvironment;
025import org.apache.hadoop.hbase.HBaseInterfaceAudience;
026import org.apache.hadoop.hbase.metrics.MetricRegistry;
027import org.apache.hadoop.hbase.wal.WAL;
028
029@InterfaceAudience.LimitedPrivate(HBaseInterfaceAudience.COPROC)
030@InterfaceStability.Evolving
031public interface WALCoprocessorEnvironment extends CoprocessorEnvironment<WALCoprocessor> {
032  /** @return reference to the region server's WAL */
033  WAL getWAL();
034
035  /**
036   * Returns a MetricRegistry that can be used to track metrics at the region server level.
037   *
038   * <p>See ExampleRegionServerObserverWithMetrics class in the hbase-examples modules for examples
039   * of how metrics can be instantiated and used.</p>
040   * @return A MetricRegistry for the coprocessor class to track and export metrics.
041   */
042  MetricRegistry getMetricRegistryForRegionServer();
043}