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 org.apache.hbase.thirdparty.com.google.protobuf.Message;
021import org.apache.yetus.audience.InterfaceAudience;
022import org.apache.yetus.audience.InterfaceStability;
023import org.apache.hadoop.hbase.HBaseInterfaceAudience;
024import org.apache.hadoop.hbase.shaded.protobuf.generated.RPCProtos.RequestHeader;
025import org.apache.hadoop.hbase.security.User;
026
027/**
028 * Function to figure priority of incoming request.
029 */
030@InterfaceAudience.LimitedPrivate({HBaseInterfaceAudience.COPROC, HBaseInterfaceAudience.PHOENIX})
031@InterfaceStability.Evolving
032public interface PriorityFunction {
033  /**
034   * Returns the 'priority type' of the specified request.
035   * The returned value is mainly used to select the dispatch queue.
036   * @param header
037   * @param param
038   * @param user
039   * @return Priority of this request.
040   */
041  int getPriority(RequestHeader header, Message param, User user);
042
043  /**
044   * Returns the deadline of the specified request.
045   * The returned value is used to sort the dispatch queue.
046   * @param header
047   * @param param
048   * @return Deadline of this request. 0 now, otherwise msec of 'delay'
049   */
050  long getDeadline(RequestHeader header, Message param);
051}