hbase-server/src/main/java/org/apache/hadoop/hbase/ipc/PluggableBlockingQueue.java

   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 package org.apache.hadoop.hbase.ipc;
  19
  20 import java.util.concurrent.BlockingQueue;
  21 import org.apache.hadoop.conf.Configuration;
  22 import org.apache.yetus.audience.InterfaceAudience;
  23 import org.apache.yetus.audience.InterfaceStability;
  24
  25 /**
  26  * Abstract class template for defining a pluggable blocking queue implementation to be used
  27  * by the 'pluggable' call queue type in the RpcExecutor.
  28  *
  29  * The intention is that the constructor shape helps re-inforce the expected parameters needed
  30  * to match up to how the RpcExecutor will instantiate instances of the queue.
  31  *
  32  * If the implementation class implements the
  33  * {@link org.apache.hadoop.hbase.conf.ConfigurationObserver} interface, it will also be wired
  34  * into configuration changes.
  35  *
  36  * Instantiation requires a constructor with {@code
  37  *     final int maxQueueLength,
  38  *     final PriorityFunction priority,
  39  *     final Configuration conf)}
  40  *  as the arguments.
  41  */
  42 @InterfaceAudience.Public
  43 @InterfaceStability.Evolving
  44 public abstract class PluggableBlockingQueue implements BlockingQueue<CallRunner> {
  45   protected final int maxQueueLength;
  46   protected final PriorityFunction priority;
  47   protected final Configuration conf;
  48
  49   public PluggableBlockingQueue(final int maxQueueLength,
  50         final PriorityFunction priority, final Configuration conf) {
  51     this.maxQueueLength = maxQueueLength;
  52     this.priority = priority;
  53     this.conf = conf;
  54   }
  55 }