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.client.backoff;
019
020import org.apache.hadoop.conf.Configuration;
021import org.apache.hadoop.hbase.ServerName;
022import org.apache.hadoop.hbase.util.ReflectionUtils;
023import org.apache.yetus.audience.InterfaceAudience;
024import org.apache.yetus.audience.InterfaceStability;
025
026@InterfaceAudience.Private
027@InterfaceStability.Evolving
028public final class ClientBackoffPolicyFactory {
029
030  private ClientBackoffPolicyFactory() {
031  }
032
033  public static ClientBackoffPolicy create(Configuration conf) {
034    // create the backoff policy
035    String className =
036      conf.get(ClientBackoffPolicy.BACKOFF_POLICY_CLASS, NoBackoffPolicy.class.getName());
037    return ReflectionUtils.instantiateWithCustomCtor(className,
038      new Class<?>[] { Configuration.class }, new Object[] { conf });
039  }
040
041  /**
042   * Default backoff policy that doesn't create any backoff for the client, regardless of load
043   */
044  public static class NoBackoffPolicy implements ClientBackoffPolicy {
045    public NoBackoffPolicy(Configuration conf) {
046      // necessary to meet contract
047    }
048
049    @Override
050    public long getBackoffTime(ServerName serverName, byte[] region, ServerStatistics stats) {
051      return 0;
052    }
053  }
054}