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.ipc;
019
020import java.util.concurrent.BlockingQueue;
021import org.apache.hadoop.conf.Configuration;
022import org.apache.yetus.audience.InterfaceAudience;
023import org.apache.yetus.audience.InterfaceStability;
024
025/**
026 * Abstract class template for defining a pluggable blocking queue implementation to be used by the
027 * 'pluggable' call queue type in the RpcExecutor. The intention is that the constructor shape helps
028 * re-inforce the expected parameters needed to match up to how the RpcExecutor will instantiate
029 * instances of the queue. If the implementation class implements the
030 * {@link org.apache.hadoop.hbase.conf.ConfigurationObserver} interface, it will also be wired into
031 * configuration changes. Instantiation requires a constructor with {@code
032 *     final int maxQueueLength,
033 *     final PriorityFunction priority,
034 *     final Configuration conf)} as the arguments.
035 */
036@InterfaceAudience.Public
037@InterfaceStability.Evolving
038public abstract class PluggableBlockingQueue implements BlockingQueue<CallRunner> {
039  protected final int maxQueueLength;
040  protected final PriorityFunction priority;
041  protected final Configuration conf;
042
043  public PluggableBlockingQueue(final int maxQueueLength, final PriorityFunction priority,
044    final Configuration conf) {
045    this.maxQueueLength = maxQueueLength;
046    this.priority = priority;
047    this.conf = conf;
048  }
049}