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1   /**
2    *
3    * Licensed to the Apache Software Foundation (ASF) under one
4    * or more contributor license agreements.  See the NOTICE file
5    * distributed with this work for additional information
6    * regarding copyright ownership.  The ASF licenses this file
7    * to you under the Apache License, Version 2.0 (the
8    * "License"); you may not use this file except in compliance
9    * with the License.  You may obtain a copy of the License at
10   *
11   *     http://www.apache.org/licenses/LICENSE-2.0
12   *
13   * Unless required by applicable law or agreed to in writing, software
14   * distributed under the License is distributed on an "AS IS" BASIS,
15   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
16   * See the License for the specific language governing permissions and
17   * limitations under the License.
18   */
19  package org.apache.hadoop.hbase.regionserver;
20  
21  import org.apache.hadoop.classification.InterfaceAudience;
22  import org.apache.hadoop.classification.InterfaceStability;
23  
24  /**
25   * A more restricted interface for HStore. Only gives the caller access to information
26   * about store configuration/settings that cannot easily be obtained from XML config object.
27   * Example user would be CompactionPolicy that doesn't need entire (H)Store, only this.
28   * Add things here as needed.
29   */
30  @InterfaceAudience.Private
31  @InterfaceStability.Unstable
32  public interface StoreConfigInformation {
33    /**
34     * @return Gets the Memstore flush size for the region that this store works with.
35     */
36    // TODO: Why is this in here?  It should be in Store and it should return the Store flush size,
37    // not the Regions.  St.Ack
38    long getMemstoreFlushSize();
39  
40    /**
41     * @return Gets the cf-specific time-to-live for store files.
42     */
43    long getStoreFileTtl();
44  
45    /**
46     * @return Gets the cf-specific compaction check frequency multiplier.
47     *         The need for compaction (outside of normal checks during flush, open, etc.) will
48     *         be ascertained every multiplier * HConstants.THREAD_WAKE_FREQUENCY milliseconds.
49     */
50    long getCompactionCheckMultiplier();
51  
52    /**
53     * The number of files required before flushes for this store will be blocked.
54     */
55    long getBlockingFileCount();
56  }