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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.client;
19  
20  import org.apache.hadoop.conf.Configuration;
21  import org.apache.hadoop.hbase.HConstants;
22  import org.apache.hadoop.hbase.util.ReflectionUtils;
23  
24  /**
25   * Factory to create an {@link RpcRetryingCaller}
26   */
27  public class RpcRetryingCallerFactory {
28  
29    /** Configuration key for a custom {@link RpcRetryingCaller} */
30    public static final String CUSTOM_CALLER_CONF_KEY = "hbase.rpc.callerfactory.class";
31    protected final Configuration conf;
32    private final long pause;
33    private final int retries;
34  
35    public RpcRetryingCallerFactory(Configuration conf) {
36      this.conf = conf;
37      pause = conf.getLong(HConstants.HBASE_CLIENT_PAUSE,
38          HConstants.DEFAULT_HBASE_CLIENT_PAUSE);
39      retries = conf.getInt(HConstants.HBASE_CLIENT_RETRIES_NUMBER,
40          HConstants.DEFAULT_HBASE_CLIENT_RETRIES_NUMBER);
41    }
42  
43    public <T> RpcRetryingCaller<T> newCaller() {
44      // We store the values in the factory instance. This way, constructing new objects
45      //  is cheap as it does not require parsing a complex structure.
46      return new RpcRetryingCaller<T>(pause, retries);
47    }
48  
49    public static RpcRetryingCallerFactory instantiate(Configuration configuration) {
50      String rpcCallerFactoryClazz =
51          configuration.get(RpcRetryingCallerFactory.CUSTOM_CALLER_CONF_KEY,
52            RpcRetryingCallerFactory.class.getName());
53      return ReflectionUtils.instantiateWithCustomCtor(rpcCallerFactoryClazz,
54        new Class[] { Configuration.class }, new Object[] { configuration });
55    }
56  }